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Objective: To investigate the effect of remote ischemic preconditioning (RIPC) on major adverse cardiovascular events (MACE) in elderly patients with hip fracture 1 year after operation., Methods: Total of 314 elderly patients with hip fracture of gradeⅡand Ⅲ for American Society of Anesthesiologists (ASA) were treated by surgical operation from April 2015 to May 2020 including 116 males and 198 females, the age ranged from 60 to 76 years old. The subjects were divided into intervention group and control group according to whether received RIPC. Among them, 157 cases in intervention group included 56 males and 101 females with an average age of (68.12±7.13) years old and 157 cases in control group included 60 males and 97 females with an average age of (68.24±7.05) years old. Both groups were given routine anesthesia. The intervention group was treated with RIPC on the basis of routine anesthesia. The MACE events 1 year after operation in two groups were compared and analyzed., Results: The OR values of RIPC for myocardial infarction, heart failure, stroke, nonfatal cardiac arrest, coronary revascularization, severe arrhythmia, peripheral artery thrombosis, readmission of cardiovascular disease, and all-cause death in patients with hip fracture one year after operation were 1.269, 1.304, 0.977, 1.089, 1.315, 1.335, 0.896, 0.774, 1.191, respectively, but there was no significant difference ( P >0.05)., Conclusion: RIPC did not significantly affect and change the occurrence of major cardiovascular adverse events within 1 year after hip fracture surgery. The long term impact of RIPC on clinical cardiovascular outcomes in non cardiac surgery needs to be confirmed in appropriate randomized clinical trials.

Objective: To investigate the correlation between estrogen related-receptorγ (ERRγ) and ATP-dependent K(+) channel Kcnj1 in renal ischemia-reperfusion injury and its possible role in regulating ischemic preconditioning. Methods: The expression of ERRγ in kidney tissues was detected by immunohistochemistry. The expressions of ERRγ and Kcnj1 in human renal tubular epithelial cells (HK-2) under hypoxia (1% O(2)) were detected by RT-PCR. The ERRγ-deficient heterozygous mice model and the ERRγ-deficient completely mice model were established. The pretreatedischemia-reperfusion model were constructed in wild-type mice, ERRγ-deficient heterozygous mice and ERRγ-deficient completely mice, respectively. Renal injury was observed under a light microscope with PAS staining. ERRγ and Kcnj1 were tested by immunohistochemistry and RT-PCR. Results: ERRγ in mice kidney tissue was mainly expressed in renal tubules, and the expressions of ERRγ and Kcnj1 were decreased 59% and 29.5% respectively after hypoxia in the renal tubular cells (HK-2). In the animal model, the expressions of ERRγ and Kcnj1 were decreased 31.9% and 11% in early ischemic mice kidney tubular cells of wild type. The expressions of ERRγ and Kcnj1 in renal tubular cells were decreased 33.2% and 19.1% after ischemia and reperfusion. When ERRγ were overexpressed in renal tubular cells, ERRγ was increased by 89%, and the expression of Kcnj1 was increased by 72.5%. The expression of Kcnj1 was decreased by 75.7% in ERRγ-deficient completely mice. However, Kcnj1 expression in renal tissue of ERR-γ-deficient mice was stable, but ischemic preconditioning failed to interfere with renal ischemia-reperfusion injury. Conclusion: ERRγ-Kcnj1 is closely related to ischemic preconditioning and protects renal ischemia-reperfusion injury, and may be one of the regulatory factors. To explore the protective effect of the regulating pathway on ischemia reperfusion injury couldprovide a theoretical basis for the development of drug pretreatment.

Objective: To investigate the effect of limb remote ischemic preconditioning (RIPC) on hepatic ischemia/reperfusion (IR) injury and the underlying mechanisms.
, Methods: Rats were subjected to partial hepatic IR (60 min ischemia followed by 24 hours reperfusion) with or without RIPC, which was achieved by 3 cycles of 10 min-occlusion and 10 min-
reperfusion at the bilateral femoral arteries interval 30 min before ischemia. Some rats were treated with a new PPAR-γ inhibitor, T0070907, before RIPC.
, Results: At the end of reperfusion, liver injury was significantly increased (increases in Suzike's injury score, AST and ALT release), concomitant with elevated oxidative stress (increases in MDA formation, MPO activity, as well as the decrease in SOD activity) and inflammation (increases in TNF-α and IL-6 levels, decrease in IL-10 content). RIPC improved liver function and reduced histologic damage, accompanied by the increased PPAR-γ activation and autophagosome formation as well as the reduced autophagosome clearance. The beneficial effects of RIPC were markedly attenuated by T0070907, an inhibitor of PPAR-γ.
, Conclusion: RIPC exerts the protective effects on liver by activation of autophagy via PPAR-γ.

Objective: To investigate the effect of simulated in vivo physiological environment severed limb fostering system applying remote ischemic conditioning (RIC) perfusion on preserving severed limb., Methods: Eighteen adult Bama mini pigs (24-30 kg in weight) were randomly divided into 3 groups (n = 6). No ischemic treatment was given in group A as normal control group; the right lower limbs were completely amputated and preserved at room temperature for 3 hours to make ischemic models in groups B and C, and then the severed limbs were put into the simulated in vivo physiological environment severed limb fostering system. Continuous blood perfusion was performed in group B, and continuous blood perfusion was performed after RIC perfusion in group C. After 8 hours of perfusion, the skeletal muscle samples were harvested for the morphology observation by transmission electron microscopy. The protein levels of B-cell lymphoma-2 (Bcl-2) and Caspase-3 were detected by Western blot. The content of cytochrome C in both mitochondria and cytoplasm was determined by ELISA., Results: Transmission electron microscopy results illustrated that the muscle fibers arranged more orderly and the mitochondria swelling was slighter in group C than group B. Western blot analysis showed that the protein levels of Bcl-2 and Caspase-3 were significantly higher in groups B and C than group A (P < 0.05); the protein level of Bcl-2 significantly increased and the protein level of Caspase-3 significantly decreased in group C when compared with those in group B (P < 0.05). ELISA detection implicated that mitochondrial cytochrome C significantly reduced and cytosolic cytochrome C significantly increased in group B when compared with those in groups A and C (P < 0.05), but no significant difference was found between group A and group C (P > 0.05)., Conclusion: The ischemia/reperfusion-induced injury to skeletal muscle could be considerably inhibited by RIG perfusion. The simulated in vivo physiological environment severed limb fostering system applying RIC perfusion can significantly prolong the severed limb preserving time.

Objective: To investigate the effect of mild hypothermia preconditioning against ischemia/reperfusion (I/R) injury of cultured primary cortical rats neurons, and to compare the protective effect of mild hypothermia only and with its combination with drugs., Methods: Cortical neurons of neonatal Sprague-Dawley (SD) rat within 24 hours after birth were harvested and cultured in vitro. On the 3rd day, the cells were cultured in a medium containing 2.5 mg/L cytosine arabinoside to inhibit the growth of glial cells and fibroblast. Having cultured for 6 days they were randomly divided into blank control group, glutamate damaged group (cultured with 200 μmol/L glutamate for 0.5 hour after washing), mild hypothermia preconditioning group (cultured under 33.5 centigrade for 24 hours before injury induced by glutamate), mild hypothermia combining with edaravone preconditioning group, and the hypothermia combining with propofol preconditioning group (medium containing 100 μmol/L edaravone and 3 mg/L propofol). They were cultured under 33.5 centigrade for 24 hours before injury induced by glutamate. After 24 hours of culturing in various medium, apoptosis ratio was observed by flow cytometry. Cell surviving rate was determined with methyl thiazolyl triazolium (MTT), c-fos protein expression was assayed, and morphologic change of cells with hematoxylin-eosin (HE) staining under the microscope, and ultrastructure changes were observed after uranyl acetate and lead citrate staining under transmission electron microscope., Results: The apoptosis ratio and c-fos protein in glutamate damaged group were significantly higher than those in blank control group [apoptosis ratio: (9.85±0.76)% vs. (0.94±0.20)%, c-fos: 6.96±0.75 ng/L vs. 1.65±0.59 ng/L, both P<0.01], the cell surviving rate was significantly lower than that in blank control group [(0.20±0.02)% vs. (0.97±0.03)%, P<0.01]. Mild hypothermia preconditioning reversed surviving rate, apoptosis ratio and c-fos protein, and the effect of hypothermia combining with propofol preconditioning was obviously better [cell surviving rate: (0.80±0.04)% vs. (0.20±0.02)%, apoptosis ratio: (2.26±0.54)% vs. (9.85±0.76)%, c-fos: 2.98±0.46 ng/L vs. 6.96±0.75 ng/L, all P<0.01]. The morphology of cortical neurons in blank control group was normal. Most of the cells in glutamate damaged group showed bluish black cytoplasm with pyknic nuclei, with crumpled axons and of them were fractured, and cell number was obviously decreased. In each pre-conditional group, decrease in cell number was unconspicuous, and only a few cells showed apoptosis. Under transmission electron microscope, it was found that cell membrane, mitochondria and rough endoplasmic reticulum were intact in blank control group, but with reduction in organelles, severely swollen mitochondria, even with formation of vacuole or pyknosis, serious dilation of rough endoplasmic reticulum, with loss of cristae with loss of vacuoles or pyknosis, and marked dilatation of internal reticular endoplasm, and loss of cristae with vacuolation and chromatin were observed under electron microscope in glutamate damaged group. Compared with the glutamate damaged group, these pathologic changes were markedly alleviated in protected groups., Conclusions: Mild hypothermia preconditioning can inhibit glutamate-induced injury to cortical neurons. The protective effect of mild hypothermia combined with propofol is better.

Objective: To explore the expression of p-p38 MAPK protein and the number of astrocytes expressing p-p38 MAPK in CA1 hippocampus in rats during the induction of brain ischemic tolerance induced by intermittent hypobaric hypoxia (IH) preconditioning., Methods: Thirty healthy adult male Wistar rats were randomly divided into 6 groups (n = 5 in each group): sham 0 min group, IH + sham 0 min group, sham 7 d group, IH + sham 7 d group, Ischemia (Is) 7 d group, and IH + Is 7 d group. Neuropathological evaluation was performed by thionine staining in CA1 hippocampus in rats. The expression of p-p38 MAPK in CA1 hippocampus was observed by immunohistochemical staining. And the number of astrocytes expressing p-p38 MAPK was observed by immunofluorescent double labeling., Results: The results showed that IH preconditioning induced brain ischemic tolerance successfully. At the same time, IH preconditioning obviously up-regulated the expression of p-p38 MAPK protein in CA1 hippocampus, and also increased the number of astrocytes expressing p-p38 MAPK., Conclusion: It might be concluded that IH preconditioning induced brain ischemic tolerance by up-regulating the expression of p-p38 MAPK protein in pyramidal neurones and astrocytes.

Objective: To study the effect of adenosine preconditioning on cell apoptosis and expressions of glucose-regulated protein (GRP-78) and cysteinyl aspartate-specific protease 12 (caspase-12) in rats with spinal cord ischemia-reperfusion injury., Methods: Twenty-seven rats were randomized into 3 equal groups and subjected to sham operation (group A), spinal cord ischemia-reperfusion injury (group B), or ischemia-reperfusion injury with adenosine treatment. Spinal cord ischemia-reperfusion injury was induced by cross-clamping of the abdominal aorta inferior to the left renal artery. The spinal cord function was assessed using the Modified Tarlov Scale at 6, 12, and 24 h after reperfusion. At 24 h after reperfusion, histological analysis was carried out with HE staining; cell apoptosis and viability were determined with TUNEL staining, and the expressions of GRP-78 and caspase-12 proteins were determined with Western blotting., Results: HE staining of the spinal cord showed extensive spinal cord injury such as cell edema in group B as compared with group C. Compared with group A, group B showed a significantly increased number of apoptotic cells; the number of apoptotic cells in group B was greater than that in group C. Compared with group B, group C showed significantly increased GRP-78 expression (P<0.01) and decreased caspase-12 expression (P<0.01)., Conclusion: Adenosine can up-regulate GRP-78 expression and down-regulate caspase-12 expression, and protects the spinal cord against ischemia-reperfusion injury by inhibiting cell apoptosis.

Objective: To investigate the effect of N-acetylcysteine (NAC) on the apoptosis during myocardial ischemia reperfusion injury in rats' heart transplantation, and to explore the possible role of NAC in myocardial apoptosis., Methods: Sixty healthy male Lewis rats (weighing, 200-220 g) were randomly divided into 3 groups, 20 rats each group (10 donors and 10 recipients). In control group, 1 mL normal saline was infused via inferior vena cava at 30 minutes before donor harvesting; in donor preconditioning group, NAC (300 mg/kg) was infused via inferior vena cava at 30 minutes before donor harvesting, but no treatment in recipients; and in recipient preconditioning group, NAC (300 mg/kg) was infused via inferior vena cava at 30 minutes before recipient transplantation, but no treatment in donors. Heart transplantation was established in each group. Blood was drawn at 6 and 24 hours after reperfusion for analysis of aspartate aminotransferase (AST), alanine aminotransferase (ALT), lactate dehydrogenase (LDH) as markers of graft injury; myocardial tissue was harvested to determine the superoxide dismutase (SOD) and lipid hydroperoxide (LPO) activity at 24 hours after reperfusion and to observe the histology and ultrastructural changes. Graft active Caspase-3 protein expression was measured by immunohistochemistry staining, and apoptosis index (AI) was calculated by TUNEL., Results: The heart transplantation operation was successfully completed in all groups, and the rats survived to the end of the experiment. The serum levels of AST, ALT, and LDH in donor and recipient preconditioning groups were significantly lower than those in control group at 6 hours after reperfusion (P < 0.05); the levels of AST and ALT in donor preconditioning group and the levels of AST and LDH in recipient preconditioning group were significantly lower than those in control group at 24 hours (P < 0.05); and no significant difference was found between donor and recipient perconditioning groups (P > 0.05). The levels of AST, ALT, and LDH at 24 hours were significantly lower than those at 6 hours in each group (P < 0.05) except the level of ALT in recipient preconditioning group (P > 0.05). SOD activity and SOD/LPO in donor and recipient preconditioning groups were significantly higher than those in control group (P < 0.05), but no significant difference between donor and recipient preconditioning groups (P > 0.05); there was no significant difference in LPO activity among 3 groups (P > 0.05). Histological staining and transmission electron microscope showed that myocardial injury in recipient preconditioning group was obviously lighter than that in donor preconditioning group and control group. Active Caspase-3 in recipient pretreatment group was significantly higher than that in donor preconditioning group and control group (P < 0.05). AI of donor and recipient preconditioning groups was significantly lower than that of control group (P < 0.05), but no significant difference was found between donor and recipient preconditioning groups (P > 0.05)., Conclusion: NAC can relieve ischemia reperfusion injury in rats' heart transplantation by improving myocardial SOD content, and reducing active Caspase-3 activity and AI, which has a protective effect on myocardial cell of donor heart.

Ischemic tolerance exists in many organs, among which the cerebral ischemic tolerance and its potential clinical applications are most notable. The discovery of new triggers of cerebral ischemic tolerance has brought more interesting insights into the molecular mechanisms. The remote ischemic preconditioning and pharmacological induction of cerebral ischemic tolerance have shown promising clinical safety and feasibility, and therefore may be important breakthroughs in the clinical application of cerebral ischemic tolerance.

Objective: To study the clinical effects of hypoxia preconditioning (HPC) and its effects on serum neuroglobin (NGB) and S-100B level in the patients undergoing intracranial aneurysm surgery., Methods: Forty patients scheduled to intracranial aneurysm surgery were randomly.divided into 2 groups: HPC group (n= 20) and control group (n= 20). The patients in HPC group were treated with 3 cycles of deoxidation-reoxygenation after intubation. The time of deoxidation in each HPC cycle was recorded, while vital signs were also recorded in each corresponding time point. Blood samples were obtained from exsanguinate radial artery and jugular bulb section at the end of each HPC cycle and corresponding time points during operation to measure serum level of NGB and S100B protein and to analysis blood gas., Results: During HPC process, the patients in group HPC experienced mild hypoxia and CO2 retention. With the times of HPC increasing, CO2 retention degree became heavier (P<0. 05) while hypoxia improved, the patients need more time to make SpO2 from 100% to 90% (P<0. 05). From T2 to T4 (the end of the third reoxygenation, during skull opened and aneurysm dipped, skull closed), NGB in group HPC was higher than that in control (P<0. 05), but S-100B level was not different between HPC and control group (P>0. 05)., Conclusion: HPC could induce compensatory ability of the body to hypoxia, which might be related to the up-regulation of NGB expression.

Objective: To investigate the effects of emulsified isoflurane preconditioning on LPS-induced acute lung injury in rats., Methods: Acute lung injury was induced by the administration of LPS 8 mg/kg intravenously in male Sprague-Dawley rats. The ratswere randomly assigned to 4 groups: LPS-induced acute lung injury group (LPS, n = 10); emulsified Isoflurane Preconditioning group (EISO, n = 10); Intralipid pre-treated group (INT, n = 10), and saline pre-reated control group (CON, n = 5). In the later 3 groups, 2 mL/kg NS, IL and EISO were infused intravenously for 30 min before the administration of LPS respectively. The animals were then observed for 5 hours. The mean arterial blood pressure(MAP) and heart rate(HR) were monitored hourly. Arterial blood gas (ABG) was measured for oxygenation index (OI) at the end of 5h. The blood samples were taken for the measurements of plasma tumor necrosis factor-alpha (TNF-alpha) and interleukin-6(IL-6). The lungs were removed for the measurements of wet/dry (W/D) weight ratio, as well as the levels of malondialdehyde (MDA), superoxide dismutase (SOD), myeloperoxidase (MPO)., Results: The OI of group CON was 435 +/- 30, group LPS 225 +/- 49, group EISO 367 +/- 41, and group INT 267 +/- 41. Compared with group CON, OI and pulmonary SOD activity significantly decreased while plasma TNF-alpha, IL-6 concentration and pulmonary MDA level, MPO activity increased in LPS, EISO and INT groups. The plasma TNF-alpha, IL-6 concentration, pulmonary MDA level and pulmonary MPO activity of group EISO were lower while OI and pulmonary SOD activity were higher than those of group LPS., Conclusion: The emulsified isoflurane pretreatment can ameliorate LPS-induced acute lung injury in rats.

Objective: To investigate how transient low dose of hydroperoxide pretreatment prevents cardiac ischemia/reperfusion injury., Methods: SD rats were divided into 4 groups: sham operation (Sham), standard ischemia/reperfusion (I/R), ischemic preconditioning (IPC) and IR preceded by low H2O2 treatment. Cardiac function and injury parameter were compared among groups., Results: IPC protected reperfusion injury and improved cardiac function. Low H2O2 treatment played a role in cardioprotection similar to IPC. Low H2O2 was indeed generated in the early phase of simulated ischemia and attenuated cytochrome c release induced by high Ca2+ in isolated mitochondria., Conclusion: Low H2O2 plays a critical role in cardioprotection probably by inhibiting mitochondrial permeability transition.

Objective: To investigate the effects of recombine human erythropoietin (rhEPO) on neural cells apoptosis and the expression of Caspase-3 protein in brain tissue of fetal rats after intrauterine hypoxic-ischemic brain injury., Methods: Forty-four Sprague-Dawley rats on 19 days of pregnancy were divided into rhEPO treated group, ischemia-reperfusion group and sham-operated group. Intrauterine hypoxic-ischemic injury of fetal rats was induced by bilateral occlusion of the utero-ovarian artery for 20 min. rhEPO (5000 U/kg) was injected into rats through caudal vein in rhEPO treated group while saline was injected into rats in hypoxic-ischemic group 30 min before hypoxic-ischemic injury. The brain samples in rhEPO treated group and hypoxic-ischemic group were obtained at 30 min, 3 h, 6 h, 24 h and 48 h respectively after artery clamping. There was no hypoxic-ischemic injury in sham-operated group, so the brain samples were obtained at 24 hours after sham operation. Neuroapoptosis in brain tissue was measured by TdT mediated dUTP-biotin nick end labeling (Tunel) staining. The expression of Caspase-3 protein was observed by immunohistochemistry., Results: The number of apoptosis cells in fetal rat hippocampus after intrauterine hypoxic-ischemic increased progressively with reperfusion. Compared with the I/R group, the number of apoptosis cells decreased in rhEPO treated group (P < 0.01). The expression of Caspase-3 increased rapidly after 3 hours from the reperfusion in the I/R group. Compared with the I/R group, there was less expression of Caspase-3 in rhEPO treated group (P < 0.01)., Conclusion: rhEPO showed the effects to inhibit the apoptosis of fetal neural cells and the expression of Caspase-3 protein due to intrauterine hypoxic-ischemic brain injury.

Objective: To observe the protective effect of Shenfu Injection (SFI) pretreatment on brain of patients receiving aortic valve replacement (AVR) undergoing cardiopulmonary bypass (CPB)., Methods: Thirty AVR patients undergoing CPB were randomly assigned to 2 groups, the control group and the experimental group, 15 cases in each group. SFI at 1.5 mL/kg (dissolved in 250 mL 5% glucose solution) was intravenously dripped to those in the experimental group 5 days before operation, once daily for 5 successive days. SFI at 1.5 mL/kg (dissolved in 250 mL 5% glucose solution) was intravenously dripped to those 30 min before anesthesia induction. Equal dose of normal saline was intravenously dripped to those in the control group, and the other procedures were the same as those for patients in the experimental group. The venous blood sample (2 mL) was drawn from the right internal carotid vein immediately after induction of anesthesia (T1),10 min after CPB (T2), 30 min after GPB (T3), 2 h after CPB (T4), 24 h after CPB (T5), and 48 h after CPB (T6), thus detecting the plasma levels of S100beta and neuron specific enolase (NSE). And patients' cognitive function was assessed with mini-mental state examination (MMSE) scale on the day before operation, the 2nd and the 7th day after operation., Results: There was no statistical difference in the levels of S1001 and NSE between the two groups at T1 (P > 0.05). There was statistical difference in the levels of S100beta and NSE between the two groups at T2, T3, T4, T5, T6, when compared with those at T1 (P <0.05). Besides, the levels of S100beta and NSE at T2, T3, T4, T5, T6 were lower in the experimental group than in the control group, showing statistical difference (P <0.05). The MMSE scores decreased on the 2nd day after operation in the two groups, showing statistical difference when compared with those on the day before operation (P <0.05). It was lowered more obviously in the control group. There was no statistical difference in the MMSE score between the 7th day post-operation and the day before operation (P >0.05)., Conclusion: SFI pretreatment had protective effect on brain in AVR patients undergoing CPB.

Objective: To investigate whether local A1R of Baihui acupoint mediate cerebral ischemia tolerance induced by electro-acupuncture (EA)., Methods: Sixty SD rats were randomly divided into five groups, i.e., the sham-operation (S) group, the model group (M), the electroacupuncture (E) group, the CCPA group and the DMSO group. The focal cerebral ischemia/reperfusion model was established by middle cerebral artery occlusion (MCAO) in rats. Rats in the E group were received EA pretreatment baihui acupoint at 2 h before established MCAO. The rats in DMSO group and the CCPA group were injected with DMSO (20 µl) and CCPA (0.1 mmol/L) 20 µl into Baihui, respectively, at 2 h before established MCAO. After 24 h reperfusion, the rats' behavior, cerebral infarct volume, the cerebral Bcl-2 protein expression were assessed., Results: Compared with M group, the rats' behavior was improved, the cerebral infarct volume was decreased and the Bcl-2 protein expression was up-regulated (P < 0.05) in the E group. Compared with M and DMSO group, the rats' behavior was improved, the cerebral infarct volume was decreased and the Bcl-2 protein expression was up-regulated (P < 0.05) in the CCPA group. There were no statistical differences between CCPA and E group., Conclusions: EA induced cerebral ischemia tolerance. Local A1R of Baihui acupoint possible mediate cerebral ischemia tolerance induced by Electroacupuncture.

Objective: To observe the effect of resveratrol and propofol, used either alone or in combination, on hepatocyte apoptosis in rats with hepatic ischemia-reperfusion injury (HIRI)., Methods: A total of 144 male SD rats were randomized into 8 equal groups, including a sham-operated group and 7 HIRI (established using Pringle method) groups with pretreatments with normal saline, Tween80, propofol (10 or 20 mg·kg(-1)·h(-1)), or resveratrol (10 or 20 mg/kg), or both propofol and resveratrol 10 min before hepatic portal vein occlusion. At 1, 3 and 6 h after the reperfusion, 6 rats from each group were sacrificed for histopathological examination of the liver tissue, detection of hepatocyte apoptosis using TUNEL assay, and measurement of Bcl-2, Bax and caspase-3 protein expressions using immunohistochemistry., Results: Compared with normal saline and Tween80, propofol and resveratrol at different doses used alone or in combination all significantly alleviated the hepatic pathologies, lowered the apoptosis index (P<0.05), increased Bcl-2 expression (P<0.05), and reduced Bax and caspase-3 expressions in the liver tissues following HIRI (P<0.05). Compared with low doses of propofol and resveratrol used alone, their combination showed more obvious protective effects against hepatocyte apoptosis (P<0.05), but at higher doses, propofol and resveratrol either alone or in combination produced similar effects., Conclusions: Propofol and resveratrol can suppress HIRI-induced hepatocyte apoptosis by up-regulating Bcl-2 and down-regulating Bax and caspase-3 expressions, and their combined use can reduce the effective doses of the drugs.

pH homeostasis is essential for development, proliferation and apoptosis of cells. Once the pH balances are broken, cell functions and survival will be affected. Nevertheless, moderate acidosis could result in adaptive responses for cell survival and increase tolerance to harmful stress. Here we found that acidic preconditioning (APC) could significantly increase the survival rate of Daphnia pulex, a freshwater invertebrate, during severe hypoxic insult. Meanwhile, the acidic treatment significantly increased the gene expression of hypoxia inducible factor (HIF). Both echinomycin, an inhibitor of HIF, and compound C, an inhibitor of AMP-activated protein kinase (AMPK), could effectively eliminate the acid-induced hypoxic tolerance and the enhanced transcription of HIF. Temsirolimus, an inhibitor of mammalian Target of Rapamycin (mTOR), though effectively abolished the increased transcription of HIF, improved the APC-mediated protection. This result suggests that the involvement of the HIF and AMPK and mTOR could signal the pathways in APC-induced protection against hypoxic insult.

Objective: To investigate the effects and mechanism of doxorubicin preconditioning in providing ischemic tolerance for rats abdomen island flaps., Methods: Twenty-four healthy adult Sprague Dawley rats, 12 males and 12 females, were randomly divided into 3 groups (n = 8): control group (group A), ischemic preconditioning group (group B), and doxorubicin preconditioning group (group C). After the abdomen island flap (6 cm x 3 cm in size) based on the superficial inferior epigastric neurovascular bundle was prepared, group A had no further treatment; group B was given a 10-minute ischemia followed by a 10-minute reperfusion for 4 times; and group C was given pretreatment with doxorubicin (1 mg/kg) by injection of the inferior epigastric vein. After 24 hours, the inferior epigastric vessels were blocked by vascular clamp for 4 hours, followed by reperfusion 2 hours to prepare ischemia/reperfusion (I/R) injury model. The rat survival was observed after operation; at 0, 8, 12, 24, and 30 hours after I/R injury, the malonyldiadehyde (MDA) and superoxide dismutase (SOD) levels were measured. At 7 days after I/R injury, the survival rate of flap were calculated and the flaps were harvested for histological observation., Results: During experiment, 5 rats died (1 rat in groups A and B respectively, 3 rats in group C) and were added. The survival rates of the flap in group A (10.10% +/- 0.43%) was lower than those in group B (91.63% +/- 1.76%) and in group C (92.75% +/- 1.48%) at 7 days after I/R injury, showing significant differences (P < 0.05), and there was no significant difference between groups B and C (t = 0.29, P = 0.77). Significant difference was found in MDA level and SOD level between group A and groups B, C after 8 hours (P < 0.05), and there was no significant difference between groups B and C (P > 0.05). Histological observation showed that inflammatory cells infiltration was more obvious and hyperplasia of fibers was weaker in group A than in groups B and C., Conclusion: Doxorubicin preconditioning can provide ischemic tolerance for rats abdomen island flaps and protect flaps from the I/R injury. The possible mechanism may be related to that doxorubicin can induce endogenous protections.

Objective: Objective to investigate the protective effects of Ligustrazine preconditioning against hepatic ischemia/reperfusion injury (IRI) in rats., Methods: Fifty male Wistar rats were randomly allocated into 3 groups: sham operation group, in which animals underwent laparotomy, experimental group and control group in which were treated with 70% IRI of the liver, especially, the animals in experimental group was given intraperitoneal injection of 2 mL Ligustrazine per day for 3 days before operation. After the operation, liver tissues were harvested at 1 h, 6 h, 24 h and 72 h for the study of histomorphological change, the respiratory control ratio (RCR) and phosphorus: oxygen ratio (P/O) of hepatocytes mitochondria, and the contents of adenosine triphosphate (ATP) of liver tissue., Results: (1) The damage hepatic tissue in experimental group was slighter than that in control group at each corresponding time-point after operation. (2) The RCR and P/O ratio at each corresponding time-point were higher in experimental group than those in control group (P < 0.05), and all of the two groups recovered after 72 h. (3) The ATP concentration in experimental group also was higher than that in control group at each corresponding time-point, and recovered faster than control group., Conclusion: The current results show that Ligustrazine preconditioning may improve energy metabolism of rat liver in ischemia reperfusion injury.

Objective: To investigate the liver protection mechanisms of MAPK signaling pathway of limb ischemia preconditioning in the late phase., Methods: Thirty-six adult male New Zealand white rabbits, weighing 1.8-2.0 kg, were randomly divided equally into 3 groups: group C (sham operation), group L (liver ischemia-reperfusion 24 h after limb ischemia preconditioning), group IR (liver ischemia-reperfusion without limb ischemia preconditioning). Serum alanine transaminase (ALT) was measured during ischemia reperfusion. The tissue and cell injury of liver were examined by optical and electron microscopy. Activation of P38MAPK, P44/P42MAPK, and JNK in hepatic tissue was assessed by western blot after 30 min of reperfusion., Results: Serum ALT and cell injury in the liver as examined by optical and electron microscopy was decreased in group L as compared with the group IR. Phosphorylation of P38MAPK, P44/ P42MAPK, and JNK were all increased significantly after 30 min of reperfusion. Phosphorylation of P38MAPK and JNK was reduced by limb ischemia pre-treatment., Conclusion: Limb ischemia pre-treatment can induce the late phase of preconditioning in rabbit liver through the inhibition of the phosphorylation of P38MAPK and JNK.

Objective: To explore the impact on cerebral protection of Trichostatin A (TSA) preconditioning in rats with middle cerebral artery occlusion (MCAO); the relationship between cerebral protection of TSA and interleukin-1 beta (IL-1β); and the impact of age on the mechanism of cerebral protection of TSA., Methods: The modified suture method was used to create stable a MCAO model. A total of 96 male SD rats were assigned randomly to four groups: a control group, a dimethyl sulfoxide (DMSO) preconditioned group, a low-dose (0.03 mg/kg) TSA-preconditioned group, and a high-dose (0.1 mg/kg) TSA-preconditioned group. Each group included four sub-groups for reperfusion for 6, 12, 24 and 48 hours, respectively, 6 rats per sub-group. An additional, eighteen healthy, male Sprague Dawley (SD) rats that received TSA preconditioning (0.1 mg/kg) were divided into three groups based on their age: young, mid-age, and old, One-way analysis of variance was used to compare the differences between groups, and the Spearman rank correlation was used to examine relationships between IL-1β concentrations in blood and cerebrospinal fluid and cerebral infarction volume., Results: The cerebral infarction volume of rats in the high-dose TSA group was less than that of the other 3 groups (P<0.05). The IL-1β in blood and the cerebrospinal fluid of rats in the highdose TSA group was lower than that in control and DMSO groups (P<0.05); for the low-dose TSA group IL-1β levels were statistically the same as in controls. The Spearman rank coefficients were 0.841 and 0.618 for cerebral infarction volume correlate to blood IL-1β and to cerebrospinal fluid IL-1β, respectively (P<0.05). No statistical differences were found in cerebral infarction volume and IL-1β levels in blood or cerebrospinal fluid (P>0.05)., Conclusion: High-dose TSA preconditioning reduces cerebral infarction volume and decreases IL- 1β levels in blood and cerebrospinal fluid; age does not affect these parameters.

The present study aimed to investigate the protective effect and mechanism of hydrogen sulfide donor NaHS administration against gastric mucosal injury induced by gastric ischemia-reperfusion (GI-R) in rats. GI-R injury was induced by clamping the celiac artery of adult male SD rats for 30 min and followed by reperfusion for 1 h. The rats were randomly divided into sham group, GI-R group, NaHS group, glibenclamide group and pinacidil group. Gastric mucosal damage was analyzed with macroscopic injured area, deep damage was assessed with histopathology scores, and the hydrogen sulfide concentration in plasma was determined by colorimetric method. The results showed that pretreatment of NaHS significantly reduced the injured area and deep damage of the gastric mucosa induced by GI-R. However, NaHS did not significantly alter the levels of hydrogen sulfide in plasma 14 d after NaHS administration. The gastric protective effect of NaHS during reperfusion could be attenuated by glibenclamide, an ATP-sensitive potassium channel (K(ATP)) blocker. However, K(ATP) opener pinacidil inhibited the GI-R-induced injury. These results suggest that exogenous hydrogen sulfide plays a protective role against GI-R injury in rats possibly through modulation of K(ATP) channel opening.

The present study was to investigate the effect of Salvia miltiorrhiza Bunge. f. alba (SMA) pharmacological pretreatment on apoptosis of cultured hippocampal neurons from neonate rats under oxygen-glucose deprivation (OGD). Cultured hippocampal neurons were randomly divided into five groups (n = 6): normal plasma group, low dose SMA plasma (2.5%) group, middle dose SMA plasma (5%) group, high dose SMA plasma (10%) group and control group. The hippocampal neurons were cultured and treated with plasma from adult Wistar rats intragastrically administered with saline or aqueous extract of SMA. The apoptosis of neurons was induced by glucose-free Earle's solution containing 1 mmol/L Na2S2O4 and labeled by MTT and Annexin V/PI double staining. Moreover, protein expressions of Bcl-2 and Bax were detected by immunofluorescence. The results showed that few apoptotic cells were observed in control group, whereas the number of apoptotic cells was greatly increased in normal plasma group and low dose SMA plasma group. Both middle and high dose SMA plasma could protect cultured hippocampal neurons from apoptosis induced by OGD (P < 0.05). The protective effect of high dose SMA plasma was stronger than that of middle one (P < 0.05). Compared to control, normal plasma and low dose SMA plasma groups, middle and high dose SMA plasma groups both showed significantly higher levels of Bcl-2 (P < 0.05 or 0.01), whereas expressions of Bax was opposite. There were no significant differences of Bcl-2 and Bax expressions between middle and high dose SMA plasma groups. Number of Bcl-2- and Bax-positive cells had similar tendency. Bcl-2/Bax (number of positive cells) ratio was higher in high dose SMA plasma group than those of all the other groups (P < 0.05 or 0.01). These results suggest that pharmacological pretreatment of blood plasma containing middle and high dose SMA could raise viability and inhibit apoptosis of OGD-injured hippocampal neurons by up-regulating the expression of Bcl-2 and down-regulating the expression of Bax.

Objective: To assess the role of p38 mitogen-activated protein kinases (p38MAPK) in the protective effect of remifentanil preconditioning (RPC) on hepatic ischemia-reperfusion injury in rats., Methods: Ninety-six male SD rats were randomly assigned into sham-operated group, ischemia-reperfusion group (I/R group), RPC group, and SB (an inhibitor of p38 MAPK) +RPC group. The rats were sacrificed at the end of reperfusion, and serum levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), tumor necrosis factor-α (TNF-α), and interleukin-1β (IL-1β) were measured. HE staining was used to observe the hepatic histopathological changes, and Western blotting was employed to examine p38MAPK and pp38MAPK protein expression. TUNEL staining was used to examine cell apoptosis in the liver tissues., Results: Compared with sham-operated group, I/R group showed significantly increased serum levels of AST, ALT, TNF-α and IL-1β with obvious histopathological changes and cell apoptosis in the liver. RPC significantly decresed the elevated serum levels of AST, ALT, TNF-α and IL-1β and lessened hepatic histopathological changes, and caused reduced p38MAPK phosphorylation and hepatic cell apoptosis index. The protective effects of RPC were abolished by SB 203580 pretreatment., Conclusion: RPC attenuates the production of inflammatory factors by activating p38MAPK signal pathway to improve hepatic ischemia-reperfusion injury, and these effects can be blocked by SB203580, a p38MAPK inhibitor.

Objective: To observe the ultrastructure changes of cerebral cortex neuron and endothelial cell in hypoxia preconditioning mice and the effects of Tongxinluo (TXL, Chinese traditional medilihe) on them., Methods: Mice were randomly divided into 4 groups: control group, hypoxia group, hypoxia preconditioning (HP) group and Tongxinluo (TXL) group. The hypoxia preconditioning mice were exposed by repetitive hypoxia for 5 runs. The animal's tolerance time of each hypoxia run was recorded. The ultrastructure change of cerebral neuron and endothelial cell were studied by electron microscope., Results: The hypoxic tolerance time in HP and TXL groups were significantly increased run by run. Compared with HP group, the tolerance time of TXL group were increased in every run. The ultrastructure of cerebral neuron and endothelial cell in hypoxia group changed obviously, mitochondrion and endoplasmic reticulum destroyed. However they were slighter in HP group than those in hypoxia group. The change in TXL group had no obvious differentce with control group and were slighter than those in HP group., Conclusion: Hypoxia preconditioning shows that organism has a strong self-repairing ability. Tongxinluo self-repairing; could increase self-repairing ability and adaptive ability of mice to hypoxia obviously.

Objective: To investigate the protection effect of bifidobacterial adhesin for intestine ischemia/reperfusion (I/R) injury on gut barrier function in rat., Methods: Seventy-two male SD rats were randomly divided into sham operation group (n = 24), I/R model group (n = 24) and pretreatment group of bifidobacterial adhesin (pretreatment group, n = 24). Six rats were anatomized at 6 h, 1 d, 4 d and 7d after inducing I/R model in each group, respectively. The pathological changes of the terminal ilea and the blood levels of TNFα, IL-6, IL-10, diamine oxidase (DAO), and the activity and content of D-lactic acid were observed., Results: The blood levels of TNFα, IL-6, DAO and D-lactic acid in I/R model group were significantly higher than sham operation group at all time points (P < 0.05), while the blood level of IL-10 was no significantly change. The activity of IL-6 and DAO in pretreatment group was significantly lower than I/R model group at all time points (P < 0.05), the blood level of TNFα in pretreatment group was significantly lower than I/R model group at 1 d, the blood level of D-lactic was significantly lower than I/R model group at 4 d and 7 d (P < 0.05). Intestinal pathological damages were obviously milder in pretreatment group than I/R model group at all time points (Chiu's pathological scores: 6 h, 3.22 ± 0.22 vs 3.57 ± 0.20; 1 d, 3.77 ± 0.13 vs 3.90 ± 0.12; 4 d, 2.93 ± 0.23 vs 3.07 ± 0.21; 7 d, 2.10 ± 0.30 vs 2.22 ± 0.17, all P < 0.05)., Conclusion: The pretreatment of bifidobacterial adhesin could protect the intestinal mucosa from I/R injury, and alleviate intestinal ischemic reperfusion injury.

Objective: To determine the mechanism of protective effect of noninvasive limb ischemic preconditioning (NIPC) on myocardium of patients with rheumatic heart disease undergoing heart valve surgery under cardiopulmonary bypass (CPB)., Methods: A total of 32 patients with rheumatic heart disease undergoing heart valve surgeries under CPB were randomly divided into 2 groups: a control group(n=16)and an NIPC group(n=16).Tourniguet was used for each patient in the NIPC group around both the upper extremities in turn, inflated for 8 min and deflated for 5 min for 3 cycles. After the anesthesia, the remaining procedures were the same as in the control group. Blood samples were collected from the central vein after the induction of anesthesia (T(1)), 5 min before aortic clamp (T(2)),30 min after aortic opening (T(3)), 6 h after the operation (T(4)), and 24 h after the operation (T(5)) to measure the concentration of cardiac troponin I and creatine kinase MB in the plasma and CGRP and ET-1 in the serum. Pathologic change of the right auricle of the heart tissue during the superior vena cave intubation and extubation was detected., Results: The content of cardiac troponin I and creatine kinase MB at T(4) and T(5) in the 2 groups was higher than that of other time points in the same group, and it reached the peak at T(5). Comparison of the content of cardiac troponin I and creatine kinase MB at T(4) and T(5) in the 2 groups showed significant difference, and that of the NIPC group was lower than the control group(P<0.05).CGRP and ET-1 contents reached the peak at T(2) in the NIPC group and at T(3) in the control group, but the peak of CGRP in the NIPC group was higher than that in the control group(P<0.01).The peak of ET-1 content in the NIPC group was lower than that in the control group(P<0.01). After the CPB, myocardial and mitochondrion impairment was lighter in the NIPC group than in the control group., Conclusion: Noninvasive limb ischemic preconditioning can protect the myocardium through increasing CGRP, inhibiting ET-1, and advancing the peak of CGRP and ET-1.

Hypoxia-inducible factor (HIF) is an important transcription factor under hypoxic condition in many organisms, and plays a key role in the induction of hypoxia tolerance. It is necessary to establish a hypoxia model for HIF and to perform further hypoxia tolerance research. To investigate the value of Daphnia as a model organism in hypoxia precondition, we developed a preconditioning protocol with a model organism, Daphnia pulex. We found that two episodes of exposure to hypoxic solution resulted in enhanced hypoxia tolerance which is dependent on HIF. Comparative genomic analysis was also made to highlight the homology of HIF-related genes among Daphnia, fruitfly and human. We found that Daphnia is suitable for the study of human hypoxic injury as a model organism.

The maintenance of the balance between oxygen supply and oxygen consumption is a key measure in preventing acute kidney hypoxic/reoxygenation injury. Morphine can inhibit metabolism and reduce the oxygen consumption. We tried to investigate the protective effects of morphine hypoxic preconditioning on acute kidney hypoxic/reoxygenation injury in rabbit and its influence on expression of caspase-3 protein. Kidney hypoxic and reoxygenation were induced by making the tested rabbits inhale 8% oxygen for three hours firstly, and then putting them in the air to breathe in normal oxygen for another three hours. Morphine hypoxic preconditioning was induced by administering morphine 3 mg/kg, and then hypoxic of 8% oxygen was induced. Caspase-3 protein expression in renal tissue was assessed by immunohistochemical method. In the present study, the expressions of caspase-3 protein were significantly higher in saline-control hypoxic group than in morphine hypoxic preconditioning group ((29.3+/-5.7)% vs. (12.16+1.23)%, P<0.05). These observations suggested that morphine hypoxic preconditioning can protect rabbit against acute kidney hypoxic/reoxygenation injury by decreasing expression of caspase-3 protein.

Objective: To investigate the effects of acupuncture pre-conditioning on apoptosis in hippocampal neurons following ischemia-reperfusion injury in aged rats., Methods: A total of 120 senile male Wistar rats aged 19 - 21 months (corresponding to 60-year-old human being) weighting 550 - 710 g were randomly divided into 4 groups (n = 30 each). Cerebral ischemic group: 4-vessel-block was conducted for 4 minutes to establish cerebral ischemic models; Acupuncture pre-conditioning group: electroacupuncture was applied at acupoint Baihui (GV20) with a frequency of 15 Hz and 2 mA for 30 minutes once daily for 5 days. Then the rats received 4-vessel-block for 4 minutes; Sham-operation group: 4 vessels were exposed; Sham-acupuncture group: only electroacupuncture for 5 days without operation. The rats were sacrificed at the end of predetermined duration of reperfusion 12 h, 1, 2, 3 and 7 d respectively. The brains were immediately harvested and hippocampal CA1 region was isolated for (1) light and electron microscopic examinations of hippocampal neurons; (2) detection of apoptotic neurons (TUNEL); (3) determination of caspase-3 protein expression with SABC (streptavidin-biotin-peroxidase complex) immuno-histochemical technique., Results: There were apoptotic neurons in all groups. The numbers of apoptotic neurons and positive neurons of caspase-3 significantly increased in the acupuncture pre-conditioning and cerebral ischemic groups versus the sham-acupuncture and sham-operation groups (P < 0.01). And the numbers of apoptotic neurons and positive neurons of caspase-3 significantly decreased in the acupuncture pre-conditioning group versus the cerebral ischemic group (P < 0.01)., Conclusion: Acupuncture pre-conditioning can decrease the neuronal apoptosis after ischemia-reperfusion injury through a lowered expression of caspase-3 protein in senile rats.

The aim of the study is to explore the effects of luteolin preconditioning on hepatic ischemia/reperfusion injury in rats and its mechanism, and investigate the effects of the change of heme oxygenase-1 (HO-1) activity on hepatic ischemia/reperfusion injury. Sprague-Dawley rats were divided into 5 groups randomly: control, model, luteolin, luteolin + zinc protoporphyrin (ZnPP, an inhibitor of HO-1) and hemin groups (n = 8 for each group). The rats in control, model and hemin groups received a standard chow daily. The rats in luteolin and luteolin + ZnPP groups received a chow supplemented with luteolin (200 mg/kg) daily. After 4 weeks, ZnPP (25 μmol/kg) and hemin (20 μmol/kg) were injected hypodermically 6 h before ischemia/reperfusion in luteolin + ZnPP and hemin groups, respectively. Portal vein and hepatic artery supplying the middle and left hepatic lobe were clamped with an atraumatic vascular clip for induction of partial hepatic ischemia in all rats except control group. After the 60 min of hepatic ischemia, a 60-minute reperfusion period was initiated by removal of the arterial clip. The levels of aspartate aminotransferase (AST) and alanine aminotransferase (ALT) were detected in serum, and the activity of superoxide dismutase (SOD) and the content of malondialdehyde (MDA) in serum and liver were measured with assay kit. The expression of HO-1 protein and activity of HO-1 were examined in liver. The results showed that the luteolin and hemin pretreatment led to significant decreased levels of AST and ALT in serum, increased activity of SOD and decreased content of MDA in serum and liver compared with model group (P < 0.01). In addition, the expression of HO-1 protein and activity of HO-1 were elevated in luteolin and hemin groups (P < 0.01). ZnPP markedly increased the levels of AST and ALT in serum, and decreased the activities of SOD and HO-1, elevated MDA content in liver when compared with those in luteolin group (P < 0.01). Cytoplasmic vacuolation and swelling of hepatocytes were revealed in the model group after ischemia/reperfusion. Treatments with luteolin and hemin markedly relieved the liver structural changes. These results suggest that HO-1 protects rat liver from ischemia/reperfusion injury, and luteolin reduces the content of MDA and increases the activity of SOD and the expression of HO-1, which indicate that luteolin can elevate the antioxidation in rat liver, and thus protects rat liver from ischemia/reperfusion injury.

Objective: To explore the protective effects of ischemic preconditioning (IPC) on the lung injury following with limbs ischemia /reperfusion (LI/R)., Methods: The models of LI/R injury were constructed in rabbits. The blood from right external jugular vein and left common carotid artery, into and out-flowing pulmonary blood (IPB, OPB) respectively. Superoxide dismutase (SOD), malondialdehyde (MDA), nitric oxide (NO) in IPB and OPB and lung tissues were measured, as well as total nitric oxide synthase (tNOS) and inducible nitric oxide synthase (iNOS) in lung tissues were detected in different groups. The effects of IPC on the lung injury were observed., Results: Compared with sham and before ischemic, the activity of SOD decreased and the content of MDA and NO increased after 4 h ischemia followed by 4 h reperfusion in IPB, OPB and lung tissues. The activity of tNOS and iNOS in lung tissues increased remarkably as well, there was statistical significance (P < 0.05, P < 0.01). SOD increased and MDA, NO, tNOS, iNOS decreased significantly by IPC before ischemia/reperfusion. The correlation analysis indicated that MDA was negatively correlated with SOD and was positively correlated with MDA, NO, iNOS (P < 0.01)., Conclusion: Oxygen free radicals metabolic confusion of lung occurred in the course of LI/R, IPC could strengthen the resistance of peroxidation in lung and had protective effects on the lung injury following with LI/R.

The aim of the present study was to investigate whether metallothionein was involved in the protection of lung ischemic preconditioning (IP) against lung ischemia-reperfusion (I/R) injury. Adult male Sprague-Dawley rats were randomly divided into 3 groups based upon the intervention (n=8): control group (C), lung I/R group (I/R), lung I/R+IP group (IP). At the end of the experiment, the content of metallothionein was tested in lung tissue. Blood specimens collected from the arteria carotis were tested for the contents of malondialdehyde (MDA), the activities of superoxide dismutase (SOD) and myeloperoxidase (MPO). The pneumocyte apoptosis index (AI) was determined by terminal deoxynucleotidyl transferase mediated dUTP nick end labeling (TUNEL). Ultrastructural changes of lung tissue were observed by using transmission electron microscope. The results showed that in I/R group, the content of metallothionein was decreased (P<0.05), the content of MDA and MPO activity were increased (P<0.01), and SOD activity was decreased (P<0.01), compared with those in control group. IP treatment significantly increased the content of metallothionein (P<0.01), attenuated the MDA level (P<0.05) and MPO activity (P<0.01), and improved SOD activity (P<0.01) in blood serum. The number of TUNEL-positive cells in IP group was significantly reduced compared with that in I/R group (P<0.01). There were abnormal ultrastructural changes in I/R group, which were markedly reversed in IP group. In conclusion, IP may protect lung against I/R injury by inducing the expression of metallothionein.

Objective: To explore the protective effect of calcium channel agonist BayK8644 preconditioning on the lungs against ischemia-reperfusion injury (I/R) and its mechanism in rabbits., Methods: Forty rabbits were randomly divided into 4 groups (10 in each group): a sham-operated group (Sham), an I/R group (I/R), an ischemic preconditioning (IP) group (IP), and a BayK8644 preconditioning group(BayK8644).The wet to dry weight (W/D) ratio, superoxide dismutase (SOD) activity, myleoperoxidase (MPO), and malondialdehyde (MDA) contents of the lung tissues were measured after the operation. Morphological and ultrastructural changes of the lung tissue were observed by light and electron microscope. The expression of pulmonary surfactant-associated protein-A (SP-A) was examined with immunohistochemistry., Results: The W/D ratio, MPO and MDA contents of the lung tissue in the BayK8644 group and IP group were significantly lower than those in the I/R group (P<0.05), while the SOD activity and expression of SP-A of the lung tissue in the BayK8644 group and IP group were significantly higher than those in the I/R group(P<0.05), The morphological changes and ultrastructural changes were less notable in the BayK8644 group and IP group, compared with the I/R group. There was no significant difference in SOD activity, MPO and MDA contents between the BayK8644 group and IP group (P>0.05)., Conclusion: Appropriate BayK8644 preconditioning can induce transient Ca²+ influx, and elicit strong protection against the lung ischemia-reperfusion injury, which can simulate the endogenous protective effect of ischemic preconditioning.

Objective: To explore the protective effect of noninvasive limb ischemic preconditioning (N-LIP) on acute lung injury (ALT) induced by lipopolysaccharide (LPS) in rats., Methods: Fifteen female SD rats were randomly divided into a control group, an acute lung injury group (ALI group), an acute lung injury and noninvasive limb ischemic preconditioning group (ALI+N-LIP group). After ALI rats were treated with N-LIP, the changes of airway resistance (AR) and dynamic compliance (Cdyn) were tested by invasive pulmonary function system and recorded. Blood samples and bronchoalveolar lavage fluid (BALF) were collected, the amounts of white blood cell (WBC) in BALF were counted by cytometry, and the level of lactate dehydrogenase (LDH) in BALF was also examined by automatic biochemistry analyzer. The level of serum superoxide dismutase (SOD) and malondialdehyd (MDA) was examined by chromatometry. The lung tissues were acquired to observe the expression of pulmonary surfactant-associated protein-A (SP-A) and pathological changes., Results: After being stimulated by methacholine (Mch), the increasing rate of AR and decreasing rate of Cdyn in the ALI+N-LIP group were less than those in the ALI group (P<0.01). The levels of WBC and LDH in BALF in the ALI+N-LIP group were much lower than those in the ALI group (P<0.05). Meanwhile, the activity of serum SOD in the ALI+N-LIP group was higher, and the level of serum MDA was lower than that in the ALI group (P<0.05). The expression of SP-A in the lung tissue in the ALI+N-LIP group was the highest in the 3 groups, while that in the ALI group was the weakest (P<0.01). Injury of the lung tissue in the ALI+N-LIP group was less than that in the ALI group, but more severe than that in the control group., Conclusion: N-LIP has protective effect on acute lung injury induced by LPS in rats. The possible mechanism is related to improving the secretion of SP-A and antioxidation.

Objective: To investigate the effects of ketamine pretreatment on cerebral edema following brain ischemia reperfusion injury in rats and assess the involvement of Aquaporin 4 (AQP4) expression., Methods: Sixty-two healthy male Sprague-Dawley rats weighing 220 -250 g were randomly divided into 3 groups: sham operation group (group Sham, n = 18); saline group (group Vehicle, n = 22); ketamine pretreatment group (group Ketamine, n = 22) . The transient focal ischemia/reperfusion was induced by introducing a silicone-coated monofilament nylon suture from the right external carotid artery into the origin of the middle cerebral artery, removing it after 90 min. In group Ketamine, the rats were exposed to ketamine (5%, 1 mg x kg(-1) x min(-1)) for 30 min before suffered from cerebral ischemia. Similarly; in group Vehicle and group Sham, the animals received saline vehicle at the same time and infusion rate. After the neurologic exams were assessed at 24 h of reperfusion, the rats were sacrificed after anesthetized, and the brains were quickly removed. To estimate cerebral edema, the wet-dry ratio was measured. Western-blot was used to detect the expression of AQP4 in the border of the infarct region., Results: The neurologic function deficit was significantly serious in group Vehicle and group Ketamine compared to group Sham (P < 0.01). Ketamine pretreatment tended to improve neurologic outcome, but there was no statistical significance. The wet-dry weight ratio and AQP4 expression increased significantly in group Vehicle and group Ketamine III than those in group Sham (P < 0.01). Compared with saline vehicle, ketamine pretreatment did not decreased the wet-dry weight ratio significantly. AQP4 expression in group Ketamine was not significantly different from group Vehicle., Conclusion: Ketamine pretreatment did not seem to improve the neurologic deficit outcome and attenuate edema, which was involved in no change of AQP4 expression.

Objective: To investigate the protective effect of morphine hypoxic preconditioning on hepatic hypoxic/reoxygenation injury in rabbits and the mechanisms involved., Methods: Hypoxic/reoxygenation injury was induced with inhalation of 8% O2 for 3 hours followed by air for 3 hours. Thirty male white New Zealand rabbits were randomly divided into 3 groups: normal control group (N group), hypoxic/reoxgenation group (H/R group) and morphine hypoxic preconditioning group (MO + H/R group). Animals in the H/R and MO + H/R groups received 5 mL of saline or 3 mg/kg of morphine respectively before the induction of hypoxic injury. Hepatic apoptosis was determined quantitatively by terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL) methods. The activity of superoxide dismulase (SOD) in liver tissues was measured at the end of reoxgygenation., Results: A large number of TUNEL positive cells [(9.50 +/- 1.00)%] were observed in hepatic tissues of rabbits in the H/R group. The administration of morphine exerted a significant anti-apoptotic effect, as evidenced by reduced TUNEL-positive staining [(2.20 +/- 0.40)%, P < 0.05 vs. H/R group]. Compared with the H/R group, treatment with morphine increased SOD activity significantly [(85.57 +/- 19.37) vs. (48.35 +/- 15.84), P < 0.05)]., Conclusion: Morphine hypoxic preconditioning can protect rabbits against acute hepatic hypoxic/ reoxygenation injury by increasing SOD activity and reducing hepatic apoptosis.

Objective: To better assess the role of p38 MAPK, this project was designed to investigate whether intraventricular injection of antisense oligodeoxynucleotide (As-ODN) directed against the p38 MAPK of pyramidal neurons in hippocampus could affect the brain ischemic tolerance induced by limb ischemic preconditioning (LIP)., Methods: The rat 4-vessel occlusion global cerebral ischemic model was used. Forty-eight male Wistar rats with permanently occlusion of the bilateral vertebral arteries were divided into 8 groups (n=6): sham, LIP, brain ischemic insult, LIP + brain ischemic insult, distilled water + LIP + brain ischemic insult, p38 MAPK As-ODN and p38 MAPK As-ODN + LIP + brain ischemic insult (two doses of 5 nmol/5 microl and 10 nmol/5 microl were used) groups. Thionin staining was used for observing histological changes of the hippocampus., Results: No significant delayed neuronal death (DND) was detected in the CA1 hippocampus of the rats that underwent sham and LIP operation. Brain ischemic insult for 8 min induced obvious DND as represented with the increase in histological grade (HG) and decrease in neuronal density (ND) significantly compared with sham and LIP groups. LIP protected the CA1 hippocampal pyramidal neurons against DND induced by global brain ischemic insult, suggesting the occurrence of brain ischemic tolerance. However, pretreatment with p38 MAPK As-ODN effectively blocked the ischemic tolerance induced by LIP in a dose dependent manner., Conclusion: It could be concluded that p38 MAPK plays an important role in the brain ischemic tolerance induced by LIP.

Objective: To determine whether the caidioprotection of acetylcholine (ACh) against ischeniia/reperftision (I/R) injury is re-kited to mitochondrial permeability transition pore (MEW) and mitochondrial AW-sensitive potassium channel (mitoK(ATP))., Methods: Male Sprague-Dawley rats were used for Langendorif isolated bean perkision. The hearts were subjected to global ischemia for 30 mm followed by 120 rein of reperfusion and the left ventricular hemodynaniic parameters were measured. Formazan, a product of 2,3, 5-triphenyl-tetrazolium chloride (TTC), which is proportional to myocardial viability, was measured at 490 nm, and the level of lactate dehydrogenase (LDH) in the coronary effluent was measured to evaluate the cardiac injury., Results: The pretreatment with ACh (0.1 mol/L, 5 mm) before I/R markedly increased myocardial formazan content, reduced LDH release, improved the recovery of the left veritficular developed pressure, +/- dP/dtmax, and rate pressure product (left ventricular developed pressure multiplied by hean rate) and attenuated the decrease of coronary flow during reperfusion. The opener of MPTP, atiractyloside (20 mmoL/L) or the inhibitor of mitoK(ATP), 5-hydroxydecanoate (100 micromol/L) abolisbed the beneficial effect of ACh., Conclusion: In the isolated rat bean, ACh protects myocardium against ischemia/reperfusion injury via inhibiting the opening of MPTP and increasing the opening of mitoKATP in heart.

Objective: To study the effect and acting mechanism of puerarin preconditioning (PP) on blood level of cytokines in patients undergoing cardiopulmonary bypass (CPB) in perioperative period., Methods: Forty patients with heart diseases scheduled to take surgical operation were randomized into the control group and the PP group equally. They were treated with the same program, excepting that 0.6 g of puerarin was given to the PP group by adding in 5% glucose solution 250 mL for intravenous dripping every day for one week before operation, but to the control group, normal saline was given instead. The levels of tumor necrosis factor-alpha (TNF-alpha), interleukin 6, 8 and 10 (IL-6, IL-8, IL-10) in arterial blood were measured at 5 time points in the process of CPB, namely, anesthetic induction (T1), 10 min after the clamp of the ascending aorta (T2), 10 min, 2 h and 12 h after the Clamped aorta is unclamped (T3, T4 and T5)., Results: All the above-mentioned indexes (TNF-alpha, IL-6, IL-8 and IL-10) gradually increased after beginning CPB, reached the peak at T4, then lowered gradually but still presented the higher levels at T5 than those at T1 (P < 0.05). Comparison between the two groups showed that levels of TNF-alpha, IL-6 and IL-8 were significantly lower (P < 0.05 or P < 0.01) and level of IL-10 was higher in the PP group than those in the control group respectively at all the time points (P < 0.01)., Conclusion: Injecting puerarin before CPB could effectively suppress the pro-inflammatory cytokines like TNF-alpha, IL-6 and IL-8; and enhance the expression of anti-inflammatory cytokines like IL-10, thus to alleviate the inflammatory reaction induced by CPB.

Objective: To investigate if sevoflurane preconditioning attenuate neuronal apoptosis induced by ischemia-reperfusion., Methods: Thirty-six male SD rats weighing 250 - 300 g were randomly divided into three groups (n = 12 each): control group (group C), ischemia-reperfusion group (group IR) (rats were established cerebral artery clamped and reperfusion model), sevoflurane preconditioning group (group S) (rats were established cerebral artery clamped and reperfusion model after 1 h 2.4% sevoflurane preconditioning). Apoptosis neurons were observed by Hematoxylin and Eosin (HE) staining and transmission electron microscope, TdT mediated Dutp nick end labeling (TUNEL) method was used to count apoptosis neurons density, fresh ischemic brain tissue was taken out, while Caspase-3 zymogen and 20 000 segment were checked by Western blot., Results: apoptosis neurons in group IR were more than ones in group S under HE staining and light microscope and transmission electron microscope, and apoptosis neurons density (cell number/0.1 mm(2)) by TUNEL staining: group C, 13.0 +/- 1.4; group IR, 189.8 +/- 6.8; group S, 110.5 +/- 4.3, the relative gray values of the contents of procaspase-3 and its 20 000 cleavage fragment were 16.72 +/- 3.0, 76.1 +/- 3.4, 51.2 +/- 3.1 and 8.2 +/- 2.3, 59.0 +/- 6.3, 31.2 +/- 5.4 respectively., Conclusions: Sevoflurane pretreatment can protect neuron on ischemia-reperfusion injury by attenuating neuronal apoptosis in rats.

Aim: To investigate the role of mitochondrial permeability transition pore (MPTP) in the cardioprotection by remote preconditioning (RPC)., Methods: Remote Precondition (RPC) was induced in anesthetized male Sprague-Dawley rats by three cycles of 5 min of right femoral artery occlusion followed by 5 min of reperfusion. Myocardial ischemia/reperfusion (I/R) injury was achieved by ligation of the left anterior descending coronary artery for 30 min and then reperfusion for 120 min. Infarct size was determined by 2,3,5-triphenyltetrazolium chloride (TTC) staining method. The level of lactate dehydragenase (LDH) in plasma and the opening of the mitochondrial permeability transition pore (MPTP) were measured., Results: RPC significantly decreased the infarct size and plasma lactate dehydrogenase level induced by I/R, and these effects were attenuated by atractyloside (Atr, 5 mg/kg), a MPTP activator. However, administration of cyclosporin A (CsA, 10 mg/kg), an inhibitor of MPTP, decreased the effect of I/R. In isolated ventricular myocytes loaded with calcein, RPC decreased the MPTP opening, and this effect was attenuated by Atr (20 micromol/L)., Conclusion: Inhibition of MPTP opening is involved in the cardioprotection by RPC.

Aim: To explore the protective effects of ischemic preconditioning on the kidney injury following with ischemia/reperfusion (I/R) of limbs., Methods: The models of I/R injury of limbs were constructed in rabbits. The blood from right external jugular vein, renal artery and renal vein represent the peripheral blood, into and out-flowing kidney blood (IKB, OKB) respectively. Superoxide dismutase (SOD), malondialdehyde (MDA), blood uria nitrogen (BUN) in peripheral blood and SOD, MDA, nitric oxide (NO) in IKB and OKB were measured, as well as SOD, MDA, induced nitric oxide synthase (iNOS) in kidney were detected in different groups. The effects of ischemic preconditioning (IPC) on the kidney injury were observed., Results: Compared with control group, the activity of SOD in peripheral blood, IKB, OKB and kidney decreased, and the content of MDA increased after 4 h ischemia followed by 4 h reperfusion. The content of BUN in peripheral blood, NO in IKB, OKB and iNOS in kidney increased remarkably as well. SOD increased and MDA, NO, BUN, iNOS decreased significantly by ischemic preconditioning (IPC) before ischemia/reperfusion. The correlation analysis indicated that MDA was negatively correlated with SOD and positively correlated with NO, BUN., Conclusion: Oxygen free radicals metabolic confusion of kidney occurred in the course of I/R of limbs, IPC could strengthen the resistance of peroxidation in kidney and had protective effects on the kidney injury following with ischemia/reperfusion (I/ R) of limbs

Aim: To investigate the protective effects of ginkgolide B and hypoxic preconditioning against acute hypoxia injury in mice., Methods: Ordinary pressure acute hypoxia model in mice was adopted to observe the ethology, the duration of the death and the degree of brain edema. Meanwhile the expression of RTP801 mRNA and erythropoietin (EPO) were measured by RT-PCR and Western blot, respectively., Results: Ginkgolide B and hypoxic preconditioning could both prolong the survival time of hypoxia under ordinary pressure,and significantly decreased the degree of brain edema. Besides ginkgolide B and hypoxic preconditioning could both up-regulate the expression of RTP801mRNA and EPO., Conclusion: Ginkgolide B has the similar effect to hypoxic preconditioning against acute hypoxia. Both of these protective effects may be associated with the up-regulation of the expression of RTP801 mRNA and EPO.

Aim: To explore the effect of propofol preconditioning on cardiomyocyte apoptosis and cytochrome C release from mitochondria during mild hypothermic ischemia/reperfusion in isolated rat hearts., Methods: 50 isolated SD rat hearts perfused on Langendorff apparatus were randomly divided into 5 groups (n=10): control group (C), DMSO group (D), 3 different concentrations of propofol groups of 25 micromol x L(-1) (P1), 50 micromol x L(-1) (P2), 100 micromol x L(-1) (P3) propofol respectively. All of the isolated rat hearts were subjected to 31 degrees C mild hypothermic ischemia for 55 min followed by 60 min reperfusion. The D, P1, P2, P3 groups were preconditioned by perfusing with K-H solution containing 20 micromol x L(-1) DMSO and 25, 50, 100 micromol x L(-1) propofol respectively for 10 min and then followed by 5 min K-H solution washing out before ischemia. The preconditioning procedure was repeated twice. Hemodynamics of the hearts was recorded after equilibration(baseline values) immediately before ischemia, 30 min and 60 min after reperfusion respectively. Cardiomyocyte apoptosis rate and contents of cytosolic and mitochondrial cytochrome C were measured at the end of reperfusion., Results: After 30 min and 60 min reperfusion, LVEDP was significantly lower and LVDP was significantly higher in P3 group than those in C group ( P < 0.05, P < 0.01). Compared with C group, cardiomyocyte apoptosis rate of the hearts decreased significantly in P2,P3 groups at the end of reperfusion (P < 0.05, P < 0.01). Cytochrome C level increased significantly in mitochondria but decreased significantly in cytosol in P2, P3 groups as compared with C group (P < 0.05, P < 0.01)., Conclusion: Propofol preconditioning decreased cardiomyocyte apoptosis, protected the heart against 31 degrees C mild hypothermic ischemia/reperfusion injury by attenuation of the release of cytochrome C from mitochondria to cytosol.

Aim: To explore the role of nitric oxide (NO) resulted from nNOS in the mGluR2/3 mediated-brain ischemic tolerance induced by cerebral ischemic preconditioning (CIP), the present study is undertaken to observe the influences of alpha-methyl-(4-tetrazolyl-phenyl) glycine (MTPG), an antagonist of mGluR2/3, on the expression of nNOS during the induction of the brain ischemic tolerance based on confirming the blocking effect of MTPG on the induction of the tolerance., Methods: Thirty-six Sprague-Dawley rats, whose vertebral arteries were permanently occluded, were randomly divided into sham, CIP, ischemic insult, CIP+ ischemic insult, MTPG+ CIP and MTPG+ CIP+ ischemic insult groups. Thionin staining and immunohistochemistry were used for neuropathological evaluation and assay of nNOS expression in the hippocampal CA1 subregion of the rats., Results: The expression of nNOS showed moderate and extreme up-regulation in the CIP and ischemia groups, respectively, compared to the sham group. The preceded CIP blocked in certain extent the extreme up-regulation of nNOS induced by brain ischemia in CIP + ischemia group. Administration of MTPG via lateral cerebral ventricle 20 min before CIP blocked the up-regulation of nNOS induced by CIP, but had no influence on the pyramidal neuronal survival. While in the MTPG+ CIP+ ischemic insult group, the expression of nNOS was stronger than that in the MTPG + CIP group, and the up-regulation was accompanied with obvious delayed neuronal death. Discussion concerned illustrated that the relative intensive up-regulation of nNOS in this group might be attributed to brain ischemia other than MTPG., Conclusion: NO resulted from nNOS participated the induction of mGluR2/3 mediated-brain ischemic tolerance as a downstream molecule of activation of mGluR2/3 during CIP.

Objective: To investigate whether the reactive oxygen species (ROS) and mitochondrial ATP-sensitive potassium (mitoKATP) channels were involved in delayed neuroprotection induced by sevoflurane on tumor necrosis factor-alpha (TNF-alpha) and interleukin-1beta (IL-1beta) levels., Methods: Eighty-four male SD rats weighing 250 approximately 280 g, undergoing thread embolism of the right middle cerebral artery occlusion (MCAO) to cause focal ischemia for 2 h and then undergoing 24 h reperfusion, were randomly divided into 7 groups (n=12, each): a sham group(S), an ischemia-reperfusion group (I/R), a sevoflurane preconditioning group (Sevo), a 2-mercaptopropionylglycine (ROS scavenger)+sevoflurane group (MPG+Sevo), a 5-hydroxydecanoate (a mitoK(ATP) blocker) + sevoflurane group (5-HD+Sevo), an MPG group, and a 5-HD group. The protein level of TNF-alpha and IL-1beta in the cerebral issue was detected by enzyme linked immunosorbent assay (ELISA) and the expression of mRNA was measured by semiquantitative reverse transcriptase polymerase chain reaction (RT-PCR)., Results: Apoptosis index (AI), the protein level and the mRNA expression of TNF-alpha and IL-1beta were significantly higher in the I/R group than those of Group S. Pre-administration of sevoflurane could inhibit the increase of the protein level and the expression of mRNA of TNF-alpha, and IL-1beta and attenuate the cerebral damage induced by ischemia-reperfusion. Neuroprotection of sevoflurane preconditioning was abolished by MPG and 5-HD. However, MPG and 5-HD alone had no effect., Conclusion: Sevoflurane can produce delayed protection against cerebral ischemia-reperfusion injury by down-regulating TNF-alpha, IL-1beta protein, and mRNA expression.

Objective: To study the effects of salidroside-pretreatment on changes of neuroethology in rats with global cerebral ischemia-reperfusion injury so as to investigate its probable mechanism., Methods: Sixty SD male rats were randomly divided into sham-operated group, untreated group and salidroside-pretreated group. The rats in salidroside-pretreated group were intraperitoneally administered with salidroside for seven days. The dose of salidroside was 12 mg/(kg.d). Thirty minutes after the last administration, the acute global cerebral ischemia-reperfusion in rats of the untreated group and the salidroside-pretreated group was induced by using the modified Pulsinelli's 4-vessel occlusion method. Five rats in each group were killed to obtain their brains 24 hours after reperfusion. The water content in the right brain was measured by calculating the ratio of dry weight to wet weight of the right brain. Activity of superoxide dismutase (SOD) and content of malondialdehyde (MDA) in hippocampus of the rats were measured. Then neurological severity scores (NSSs) of the other 15 rats in each group were observed respectively before and 6, 12, 24, 48 and 96 h after reperfusion. At the fifth day after reperfusion, the test of Morris water maze was carried out to examine the memories and learning abilities of the rats., Results: The content of MDA, the activity of SOD, the NSS, the mean incubation period and the ratio of time in the second quadrant in the untreated group were significant different from those in the sham-operated group (P<0.05). Compared with the untreated group, the brain water content, the content of MDA and the NSS degraded, and the mean incubation period shortened in salidroside-pretreated group. The activity of SOD and the ratio of residence time in the second quadrant increased in salidroside-pretreated group as compared with the untreated group (P<0.05)., Conclusion: Salidroside can reduce the degree of cerebral edema of rats with global cerebral ischemia-reperfusion injury, relieve the metabolism abnormity of free radical and improve the function of cognition.