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Autophagy is regulated by nutrient and energy status and plays an adaptive role during nutrient deprivation and ischemic stress. Metabolic syndrome (MetS) is a hypernutritive state characterized by obesity, dyslipidemia, elevated fasting blood glucose levels, and insulin resistance. It has also been associated with impaired autophagic flux and larger-sized infarcts. We hypothesized that dietinduced obesity (DIO) affects nutrient sensing, explaining the observed cardiac impaired autophagy. We subjected male friend virus B NIH (FVBN) mice to a high-fat diet, which resulted in increased weight gain, fat deposition, hyperglycemia, insulin resistance, and larger infarcts after myocardial ischemia-reperfusion. Autophagic flux was impaired after 4 wk on a high-fat diet. To interrogate nutrientsensing pathways, DIO mice were subjected to overnight fasting, and hearts were processed for biochemical and proteomic analysis. Obese mice failed to upregulate LC3-II or to clear p62/SQSTM1 after fasting, although mRNA for LC3B and p62/SQSTM1 were appropriately upregulated in both groups, demonstrating an intact transcriptional response to fasting. Energy- and nutrient-sensing signal transduction pathways [AMPK and mammalian target of rapamycin (mTOR)] also responded appropriately to fasting, although mTOR was more profoundly suppressed in obese mice. Proteomic quantitative analysis of the hearts under fed and fasted conditions revealed broad changes in protein networks involved in oxidative phosphorylation, autophagy, oxidative stress, protein homeostasis, and contractile machinery. In many instances, the fasting response was quite discordant between lean and DIO mice. Network analysis implicated the peroxisome proliferator-activated receptor and mTOR regulatory nodes. Hearts of obese mice exhibited impaired autophagy, altered proteome, and discordant response to nutrient deprivation. [ABSTRACT FROM AUTHOR]

The focus for this clinical review is under-prescribing and non-adherence to medication guidelines in older adults after coronary artery bypass grafting (CABG) surgery. Non-adherence occurs in all age groups, but older adults have a unique set of challenges including difficulty hearing, comprehending, and remembering instructions; acquiring and managing multiple medications; and tolerating drug-drug and drug-disease interactions. Still, nonadherence leads to increased morbidity, mortality, and costs to the healthcare system. Factors contributing to non-adherence include failure to initiate therapy before hospital discharge; poor education about the importance of each medication by hospital staff; poor education about medication side effects; polypharmacy; multiple daily dosing; excessive cost; and the physician's lack of knowledge of clinical indicators for use of medications. To improve adherence, healthcare systems must ensure that (i) all patients are prescribed the appropriate medications at discharge; (ii) patients fill and take these medications post-operatively; and (iii) patients continue long-term use of these medications. Interventions must target central administrative policies within healthcare institutions, the difficulties facing providers, as well as the concerns of patients. Corrective efforts need to be started early during the hospitalization and involve practitioners who can follow patients after the date on which surgical care is no longer needed. A solid, ongoing relationship between patients and their primary-care physicians and cardiologists is essential. This review summarizes the post-operative medication guidelines for CABG surgery, describes barriers that limit the adherence to these guidelines, and suggests possible avenues to improve medication adherence in older cardiac surgery patients. [ABSTRACT FROM AUTHOR]

The article offers information on a study which investigated the potential role of autophagy in myocardial ischemia-reperfusion injury. Data presented reveal that autophagy, or the endogenous strictly-regulated cellular process involved in damaged and dysfunctional cellular organelles and protein aggregates, is potentially an adaptive process that provides enhanced resistance to ischemia-reperfusion injury. The study summarizes the process of autophagy and presents the advantages and disadvantages of autophagy-mediated cardioprotection.

The study of autophagy has been transformed by the cloning of most genes in the pathway and the introduction of GFP-LC3 as a reporter to allow visual assessment of autophagy. The field of cardiac biology is not alone in attempting to understand the implications of autophagy. The purpose of this review is to address some of the controversies and conundrums associated with the evolving studies of autophagy in the heart. Autophagy is a cellular process involving a complex orchestration of regulatory gene products as well as machinery for assembly, selective targeting, and degradation of autophagosomes and their contents. Our understanding of the role of autophagy in human disease is rapidly evolving as investigators examine the process in different tissues and different pathophysiological contexts. In the field of heart disease, autophagy has been examined in the settings of ischemia and reperfusion, preconditioning, cardiac hypertrophy, and heart failure. This review addresses the role of autophagy in cardioprotection, the balance of catabolism and anabolism, the concept of mitochondrial quality control, and the implications of impaired autophagic flux or frustrated autophagy. [ABSTRACT FROM AUTHOR]

Previously, we showed that sulfaphenazole (SUL), an antimicrobial agent that is a potent inhibitor of cytochrome P4502C9, is protective against ischemia-reperfusion (TIR) injury (Ref. 15). The mechanism, however, underlying this cardioprotection, is largely unknown. With evidence that activation of autophagy is protective against simulated hR in HL-1 cells, and evidence that autophagy is upregulated in preconditioned hearts, we hypothesized that SUL-mediated cardioprotection might resemble ischemic preconditioning with respect to activation of protein kinase C and autophagy. We used the Langendorff model of global ischemia to assess the role of autophagy and protein kinase C in myocardial protection by SUL during hR. We show that SUL enhanced recovery of function, reduced creatine kinase release, decreased infarct size, and induced autophagy. SUL also triggered PKC translocation, whereas inhibition of PKC with chelerythrine blocked the activation of autophagy in adult rat cardiomyocytes. In the Langendorff model, chelerythrine suppressed autophagy and abolished the protection mediated by SUL. SUL increased autophagy in adult rat cardiomyocytes infected with GFP-LC3 adenovirus, in isolated perfused rat hearts, and in mCherry-LC3 transgenic mice. To establish the role of autophagy in cardioprotection, we used the cellpermeable dominant-negative inhibitor of autophagy, Tat-Atg5K130R. Autophagy and cardioprotection were abolished in rat hearts perfused with recombinant Tat-Atg5K130R Taken together, these studies indicate that cardioprotection mediated by SUL involves a PKC-dependent induction of autophagy. The findings suggest that autophagy may be a fundamental process that enhances the heart's tolerance to ischemia. [ABSTRACT FROM AUTHOR]

Autophagy is a critical cellular housekeeping process that is essential for removal of damaged or unwanted organelles and protein aggregates. Under conditions of starvation, it is also a mechanism to break down proteins to generate amino acids for synthesis of new and more urgently needed proteins. In the heart, autophagy is upregulated by starvation, reactive oxygen species, hypoxia, exercise, and ischemic preconditioning, the latter a well-known potent cardioprotective phenomenon. The observation that upregulation of autophagy confers protection against ischemia/reperfusion injury and inhibition of autophagy is associated with a loss of cardioprotection conferred by pharmacological conditioning suggests that the pathway plays a key role in enhancing the heart’s tolerance to ischemia. While many of the antecedent signaling pathways of preconditioning are well-defined, the mechanisms by which preconditioning and autophagy converge to protect the heart are unknown. In this review we discuss mechanisms that potentially underlie the linkage between cardioprotection and autophagy in the heart. [ABSTRACT FROM AUTHOR]

Sodium–glucose cotransporter 2 (SGLT2) inhibitors such as empagliflozin are known to reduce the risk of hospitalizations related to heart failure irrespective of diabetic state. Meanwhile, adverse cardiac remodeling remains the leading cause of heart failure and death in the USA. Thus, understanding the mechanisms that are responsible for the beneficial effects of SGLT2 inhibitors is of the utmost relevance and importance. Our previous work illustrated a connection between adverse cardiac remodeling and the regulation of mitochondrial turnover and cellular energetics using a short-acting glucagon-like peptide-1 receptor agonist (GLP1Ra). Here, we sought to determine if the mechanism of the SGLT2 inhibitor empagliflozin (EMPA) in ameliorating adverse remodeling was similar and/or to identify what differences exist, if any. To this end, we administered permanent coronary artery ligation to induce adverse remodeling in wild-type and Parkin knockout mice and examined the progression of adverse cardiac remodeling with or without EMPA treatment over time. Like GLP1Ra, we found that EMPA affords a robust attenuation of PCAL-induced adverse remodeling. Interestingly, unlike the GLP1Ra, EMPA does not require Parkin to improve/maintain mitochondria-related cellular energetics and afford its benefits against developing adverse remodeling. These findings suggests that further investigation of EMPA is warranted as a potential path for developing therapy against adverse cardiac remodeling for patients that may have Parkin and/or mitophagy-related deficiencies. [ABSTRACT FROM AUTHOR]

The mechanism by which distinct stimuli activate the same mitogen-activated protein kinases (MAPKs) is unclear. We examined compartmentalized MAPK signaling and altered redox state as possible mechanisms. Adult rat cardiomyocytes were exposed to the adenosine , receptor agonist 2-chloro-N6-cyclopentyladenosine (CCPA; 500 nM) or H202 (100 μM) for 15 min. Nuclear/myofilament, cytosolic, Triton-soluble membrane, and Triton-insoluble membrane fractions were generated. CCPA and H202 activated p38 MAPK and p44/p42 ERKs in cytosolic fractions. In Triton-soluble membrane fractions, H202 activated p38 MAPK and p42 ERK, whereas CCPA had no effect on MAPK activation in this fraction. The greatest difference between H202 and CCPA was in the Triton-insoluble membrane fraction, where H202 increased p38 and p42 activation and CCPA reduced MAPK activation. CCPA also increased protein phosphatase 2A activity in the Triton-insoluble membrane fraction, suggesting that the activation of this phosphatase may mediate CCPA effects in this fraction. The Triton-insoluble membrane fraction was enriched in the caveolae marker caveolin-3, and >85% of p38 MAPK and p42 ERK was bound to this scaffolding protein in these membranes, suggesting that caveolae may play a role in the divergence of MAPK signals from different stimuli. The antioxidant N-2-mercaptopropionyl glycine (300 μM) reduced H202-mediated MAPK activation but failed to attenuate CCPA-induced MAPK activation. H2O2 but not CCPA increased reactive oxygen species (ROS). Thus the adenosine A1 receptor and oxidative stress differentially modulate subcellular MAPKs, with the main site of divergence being the Triton-insoluble membrane fraction. However, the adenosine A, receptor-mediated MAPK activation does not involve ROS formation. [ABSTRACT FROM AUTHOR]

There is increasing evidence for interactions among adenosine receptor subtypes in the brain and heart. The purpose of this study was to determine whether the adenosine A2a receptor modulates the infarct size-reducing effect of preischemic administration of adenosine receptor agonists in intact rat myocardium. Adult male rats were submitted to in vivo regional myocardial ischemia (25 mm) and 2 h reperfusion. Vehicle-treated rats were compared with rats pretreated with the A1 agonist 2-chloro-N6-cyclopentyladenosine (CCPA, 10 µg/kg), the nonselective agonist 5′-N-ethylcarboxamidoadenosine (NECA, 10 µg/kg), or the A2a agonist 2-[4-(2-carboxyethyl)phenethylamino]-5′-N-methylcarboxamidoadenosine (CGS-2 1680, 20 µg/kg). Additional CCPA- and NECA-treated rats were pretreated with the A antagonist 8-cyclopentyl-1,3-dipropylxanthine (DPCPX, 100 µg/kg), the A2a/A2b antagonist 4-(-2-[7-amino-2-{2-furyl} {1,2,4) triazolo{2,3-a}{1,3,5) triazin-5-yl-aminolethyl)phenol (ZM-241385, 1.5 mg/kg) or the A3 antagonist 3-propyl-6-ethyl-5[(ethylthio)carbonyl]-2-phenyl-4-propyl-3-pyridine carboxylate (MRS-1523, 2 mg/kg). CCPA and NECA reduced myocardial infarct size by 50% and 35%, respectively, versus vehicle, but COS-21680 had no effect. DPCPX blunted the bradycardia associated with CCPA and NECA, whereas ZM-241385 attenuated their hypotensive effects. Both DPCPX and ZM-241385 blocked the protective effects of CCPA and NECA. The A3 antagonist did not alter the hemodynamic effects of CCPA or NECA, nor did it alter adenosine agonist cardioprotection. None of the antagonists alone altered myocardial infarct size. These findings suggest that although preischemic administration of an A2a receptor agonist does not induce cardioprotection, antagonism of the A2a and/or the A2b receptor blocks the cardioprotection associated with adenosine agonist pretreatment. [ABSTRACT FROM AUTHOR]

Background: An earlier study of our faculty's evaluation of junior medical students indicated that performance ratings were unreliable and reflected 1 underlying dimension. Other researchers have obtained similar results. Purpose: The purpose of this study was to identify which aspects of students' clinical performance faculty actually observe. Methods: We analyzed the responses of 9 faculty members to an open-ended questionnaire concerning which aspects of clinical performance attending faculty observe. We also reviewed and summarized the written comments of 331 faculty evaluations of third-year medical students. Results: Analysis of the questionnaires and evaluations indicated that faculty members gauge medical knowledge, professionalism, and clinical reasoning skills from direct interaction with students. History-taking and physical examination skills are inferred from the quality of verbal presentations. Faculty have little basis for evaluating other important aspects of clinical performance. Conclusions: Faculty primarily observe medical students' cognitive skills and professionalism. Faculty have little basis for evaluating most other features of clinical performance. [ABSTRACT FROM AUTHOR]

The purpose of this study was to determine whether aged myocardium exhibits decreased responsiveness to adenosine A1 and A(2a) receptor activation. Studies were conducted in adult (4-6 months) and aged (24-26 months) Fischer 344 x Brown Norway hybrid (F344 x BN) rats. Effects of the adenosine A1/A(2a) agonist AMP579 were measured in isolated hearts and in rats submitted to in vivo regional myocardial ischemia. Aged isolated hearts exhibited lower spontaneous heart rates and higher coronary resistance, as well as normal A1- and A(2a)-mediated responses. There was no difference in control infarct size between adult and aged rats; however, AMP579 treatment resulted in a 50% greater infarct size reduction in aged rats (18 +/- 4% of risk area) compared to adult rats (37 +/- 3%). These findings suggest that adenosine A1 and A(2a) receptor-mediated effects are not diminished in normal aged myocardium, and that aged hearts exhibit increased adenosine agonist-induced infarct reduction. [ABSTRACT FROM AUTHOR]

Adenosine A1 receptor delayed preconditioning (PC) against myocardial infarction has been well described; however, there have been limited investigations of the signaling mechanisms that mediate this phenomenon. In addition, there are multiple conflicting reports on the role of inducible nitric oxide synthase (iNOS) in mediating A1 late-phase PC. The purpose of this study was to determine the roles of the p38 and extracellular signal-regulated kinase (ERK) mitogen-activated protein kinases (MAPKs) in in vivo delayed A1 receptor PC and whether this protection at the myocyte level is due to upregulation of iNOS. Myocardial infarct size was measured in open-chest anesthetized rats 24 h after treatment with vehicle or the adenosine A1 agonist 2-chloroN6-cyclopentyladenosine (CCPA; 100 µg/kg ip). Additional rats receiving CCPA were pretreated with the p38 inhibitor SB-203580 (1 mg/kg ip) or the MAPK/ERK kinase (MEK) inhibitor PD-098059 (0.5 mg/kg ip). At 24 h after CCPA administration, a group of animals was given the iNOS inhibitor 1400W 10 min before ischemia. Treatment with CCPA reduced infarct size from 48 ± 2 to 28 ± 2% of the area at risk, an effect that was blocked by both SB-203580 and PD-098059 but not 1400W. Ventricular myocytes isolated 24 h after CCPA injection exhibited significantly reduced oxidative stress during H2O2 exposure compared with myocytes from vehicle-injected animals, and this effect was not blocked by the iNOS inhibitor 1400W. Western blot analysis of whole heart and cardiac myocyte protein samples revealed no expression of iNOS 6 or 24 h after CCPA treatment. These results indicate that adenosine A1 receptor delayed PC in rats is mediated by MAPK-dependent mechanisms, but this phenomenon is not associated with the early or late expression of iNOS. [ABSTRACT FROM AUTHOR]

The protective effects of adenosine receptor acute preconditioning (PC) are well known; however, the signaling mechanism mediating this effect has not been determined in in vivo models. The purpose of this study was to determine the role of the extracellular signal-regulated kinase (ERK) pathway in mediating adenosine PC in in vivo rat myocardium. Open-chest rats were submitted to 25 mm of coronary artery occlusion and 2 h of reperfusion. ERK activation was assessed by measuring total and dually phosphorylated p44/42 ERK isoforms in nuclear and/or myofilament, mitochondrial, cytosolic, and membrane fractions. Adenosine receptor PC with the A1/A2a agonist 1S-[1a,2b,3b,4a(S∗) methylpropyl]amino]-3H-imidazo[4,5-b]pyridyl-3-yl]cyclopentane carboxamide (AMP-579) reduced infarct size from 49 ± 3% to 29 ± 3%, an effect that was blocked by the mitogen-activated protein kinase-ERK inhibitor U-0126. ERK isoforms were present in all fractions, with the greatest expression in the cytosolic fraction and the least in the mitochondrial fraction. AMP-579 treatment increased preischemic p44/42 ERK phosphorylation in all fractions 2.7- to 6.9-fold. Reperfusion increased ERK isoform activation in all fractions, but there were no differences between control and AMP-579 hearts. Preischemic increases in phospo-p44/p42 ERK with AMP-579 were blunted by U-0126, although only in mitochondrial and membrane compartments. The PC effects of AMP-579 on infarct size and ERK were blunted by both the A1 antagonist 8-cyclopentyl-1,3-dipropylxanthine and, surprisingly, the A2a antagonist ZM-241385. These results indicate that the unique adenosine receptor agonist AMP-579 exerts its beneficial effects in vivo via both A1 and A2a receptor modulation of subcellular ERK isoform signaling. [ABSTRACT FROM AUTHOR]

Although acute adenosine preconditioning (PC) is well established, the signaling pathways mediating this cardioprotection remain unclear. Because adenosine receptor agonists activate p38 MAPK and this kinase has been implicated in ischemic and pharmacological PC, the purpose of this study was to determine the role of p38 MAPK in acute adenosine receptor PC. The role of p38 MAPK activation in discrete subcellular compartments during ischemia-reperfusion was also determined. The following groups were used in an in vivo rat ischemia-reperfusion model: 1) control (10% DMSO iv), 2) the A1/A2a adenosine receptor AMP-579 (50 μg/kg iv), 3) AMP-579 + the A1 receptor antagonist 8-cyclopentyl-1,3-dipropylxanthine (DPCPX, 100 μg/kg iv), 4) AMP-579 + the p38 MAPK inhibitor SB-203580 (1 mg/kg iv), and 5) SB-203580 alone. p38 MAPK activation was measured by Western blot analysis in cytosolic, mitochondrial, membrane, and nuclear/myofilament fractions obtained from hearts at preischemic, ischemic, and reperfusion time points. A significant reduction in infarct size was observed with AMP-579 PC, an effect blocked by DPCPX or SB-203580 pretreatment. AMP-579 treatment was associated with a significant increase in p38 MAPK activation in the nuclear/myofilament fraction before ischemia, whereas no activation of this kinase occurred during ischemia or reperfusion. In contrast, p38 MAPK was activated in the mitochondrial fraction by ischemia and in the cytosolic, mitochondrial, and membrane fractions by reperfusion in the control group. SB-203580 blocked the AMP-579-induced increase in phosphorylation of the downstream p38 substrate activating transcription factor-2. These results suggest a role for p38 MAPK activation in discrete subcellular compartments in acute adenosine A1 receptor PC. [ABSTRACT FROM AUTHOR]

: BackgroundInhibition of the sodium-hydrogen exchanger isoform 1 with HOE-642 (cariporide) has been shown to protect against ischemia-reperfusion injury and to decrease myocardial cell death in numerous animal preparations; however the effects of cariporide in stunned myocardium are not as well understood. We sought to determine whether cariporide attenuated myocardial stunning in vivo.: MethodsOpen chest anesthetized pigs (22–33 kg) were subjected to 15 min of left anterior descending coronary artery (LAD) occlusion followed by 3 h of reperfusion. Regional ventricular function was assessed by segment shortening. Contractility was measured by stroke work and by load-insensitive preload recruitable stroke work and preload recruitable stroke work area. Vehicle or HOE-642 (1 mg/kg, IV) was administered 10 min before LAD occlusion.: ResultsCariporide treatment significantly improved postischemic segment shortening, stroke work, preload recruitable stroke work, and preload recruitable stroke work area and had no systemic hemodynamic effects. After 3 h of reperfusion, control animals recovered 33% ± 4% and 33% ± 3% of preischemic LAD segment shortening and preload recruitable stroke work area values, respectively, whereas animals treated with HOE-642 recovered 59% ± 6% and 57% ± 6%, respectively (p < 0.05). Seven (39%) of 17 control animals exhibited ventricular fibrillation during reperfusion; none of the cariporide-treated pigs fibrillated.: ConclusionsSodium–hydrogen exchange inhibition can attenuate postischemic myocardial stunning in addition to its well-described anti-infarct properties. Inhibition of the sodium–hydrogen exchanger may be beneficial in patients susceptible to postischemic myocardial dysfunction associated with cardiac surgery. [Copyright &y& Elsevier]

The intermediary metabolite pyruvate attenuates stunning and reduces infarct size in in vivo porcine myocardium. Am J Physiol Heart Circ Physiol 286: H517–H524, 2004. First published October 9, 2003; 10.1152/ajpheart.00777.2003.—The intermediary metabolite pyruvate has been shown to exert significant beneficial effects in in vitro models of myocardial oxidative stress and ischemia-reperfusion injury. However, there have been few reports of the ability of pyruvate to attenuate myocardial stunning or reduce infarct size in vivo. This study tested whether supraphysiological levels of pyruvate protect against reversible and irreversible in vivo myocardial ischemia-reperfusion injury. Anesthetized, open-chest pigs (n = 7/group) underwent 15 rain of left anterior descending coronary artery (LAD) occlusion and 3 h of reperfusion to induce stunning. Load-insensitive contractility measurements of regional preload recruitable stroke work (PRSW) and PRSW area (PRSWA) were generated. Vehicle or pyruvate (100 mg/kg iv bolus + 10 mg·kg−¹-min−¹ intra-atrial infusion) was administered during ischemia and for the first hour of reperfusion. In infarct studies, pigs (n = 6/group) underwent 1 h of LAD ischemia and 3 h of reperfusion. Group I pigs received vehicle or pyruvate for 30 min before and throughout ischemia. In group H, the infusion was extended through 1 h of reperfusion. In the stunning protocol, pyruvate significantly improved the recovery of PRSWA at 1 h (50 ± 4% vs. 23 ± 3% in controls) and 3 h (69 ± 5% vs. 39 ± 3% in controls) reperfusion. Control pigs exhibited infarct sizes of 66 ± 1% of the area at risk. The pyruvate I protocol was associated with an infarct size of 49 ± 3% (P < 0.05), whereas the pyruvate II protocol was associated with an infarct size of 30 ± 2% (P < 0.05 vs. control and pyruvate I). These findings suggest that pyruvate attenuates stunning and decreases myocardial infarction in vivo in part by reduction of reperfusion injury. Metabolic interventions such as pyruvate should be considered when designing the optimal therapeutic strategies for limiting myocardial ischemia-reperfusion injury. [ABSTRACT FROM AUTHOR]

Presents a study that examined the application of the National Surgical Quality Improvement Program (NSQIP) methods in non-Veterans Affairs hospitals to determine whether similar improvements in surgical outcomes can be realized in the nonfederal sector. Background on the NSQIP system; Ratio of expected deaths in the hospitals; Significance of safety-related events after major surgical operations to the morbidity and mortality of patients.

Background. There have been numerous studies examining the role of nitric oxide (NO) in myocardial ischemia-reperfusion injury; however, few studies have included measurements of NO or related reactive nitrogen species. The purpose of this study was to determine the effects of in vivo regional myocardial ischemia on interstitial fluid (ISF) reactive nitrogen species.Methods. Open chest pigs were submitted to one of three protocols: (1) 15 minutes coronary occlusion and 2 hours reperfusion, (2) 60 minutes coronary occlusion and 2 hours reperfusion, or (3) two-cycle ischemic preconditioning (IPC) followed by prolonged ischemia and 2 hours reperfusion. The stable NO metabolites, nitrite plus nitrate (NOx), in cardiac microdialysis samples were measured by ozone chemiluminescence.Results. NOx concentration decreased 40% ± 6% (p < 0.05) during brief ischemia but returned to baseline during reperfusion. Dialysate NOx levels decreased further after 60 minutes ischemia (60% ± 3% of baseline, p < 0.01) but reperfusion dialysate NOx concentration increased 34% ± 9% above baseline (p < 0.05). Preconditioning did not increase dialysate NOx but did accelerate the ischemia-induced decrease in NOx levels (p < 0.05). Reperfusion NOx levels in preconditioned pigs were significantly lower than in nonpreconditioned pigs (p < 0.05).Conclusions. These results suggest that ischemia is associated with decreased ISF NOx concentration. Reperfusion NOx levels are increased after prolonged ischemia, an effect that is significantly blunted by ischemic preconditioning. [Copyright &y& Elsevier]

Discusses a study that determined whether adenosine (A[sub2a]) receptors are expressed in rat ventricular myocytes. Physiological effects that are mediated via activation of adenosine receptors; Method used to investigate the presence of A[sub2a] receptors in cells; Results and discussion.

Explains how annexin V-propidium iodide staining is used to examine apoptosis and necrosis after simulated ischemia (SIsc) and simulated reperfusion (SRP) in rat ventricular myocytes. Isolation of ventricular myocytes; Results of the staining experiment after 20 or 60 minutes of simulated ischemia; Effects of 20-minute SIsc, followed by 20- or 60- min SRP on the percentage of cardiomyocytes staining positive for annexin V.

Presents a study which determined the role of of A[sub 1] agonist 8-cyclopentyl-1,3,-dipropylxanthine in adenosine A[sub 1] agonist cardioprotection. Methodology; Results; Discussion.

Presents information on a study which determined whether the protein phosphatase inhibitor cantharidin blocks the anti-adrenergic effects of adenosine A receptor in rat cardiac myocytes. Role of cellular cyclic adenosine monophosphate in the anti-adrenergic effect of cyclopentyladenosine; Methodology of the study; Results and discussion.

Cardiovascular disease is the main cause of death worldwide, making it crucial to search for new therapies to mitigate major adverse cardiac events (MACEs) after a cardiac ischemic episode. Drugs in the class of the glucagon-like peptide-1 receptor agonists (GLP1Ra) have demonstrated benefits for heart function and reduced the incidence of MACE in patients with diabetes. Previously, we demonstrated that a short-acting GLP1Ra known as DMB (2-quinoxalinamine, 6,7-dichloro-N-[1,1-dimethylethyl]-3-[methylsulfonyl]-,6,7-dichloro-2-methylsulfonyl-3-N-tert-butylaminoquinoxaline or compound 2, Sigma) also mitigates adverse postinfarction left ventricular remodeling and cardiac dysfunction in lean mice through activation of parkin-mediated mitophagy following infarction. Here, we combined proteomics with in silico analysis to characterize the range of effects of DMB in vivo throughout the course of early postinfarction remodeling. We demonstrate that the mitochondrion is a key target of DMB and mitochondrial respiration, oxidative phosphorylation and metabolic processes such as glycolysis and fatty acid beta-oxidation are the main biological processes being regulated by this compound in the heart. Moreover, the overexpression of proteins with hub properties identified by protein–protein interaction networks, such as Atp2a2, may also be important to the mechanism of action of DMB. Data are available via ProteomeXchange with identifier PXD027867. [ABSTRACT FROM AUTHOR]

Evaluates the safety, tolerance and efficacy of adenosine as an additive to blood cardioplegia in humans during coronary artery bypass surgery. Effect of adenosine addition on plasma adenosine, inosine and hypoxanthine levels; Influence of the adenosine additive on regional wall motion and global function assessed by transthoracic echocardiography.

Investigates the effect of pyruvates on calcium transients and cell shortening in rat ventricular myocytes. Effects of pyruvate on cell shortening and intracellular calcium concentration; Influence of supraphysiological glucose and insulin on intracellular calcium concentration and cell shortening.

This report describes the successful repair of a ruptured abdominal aortic aneurysm (AAA) associated with a horseshoe kidney (HK). The operative management of this problem is discussed. The preoperative evaluation of patients in whom an AAA and HK are known to coexist, the indications for elective aneurysm resection, and the operative management of this problem are examined. [ABSTRACT FROM AUTHOR]

The celiac artery compression syndrome (or median arcuate ligament syndrome) is characterized by postprandial abdominal pain, an epigastric bruit, and arteriographic evidence of significant extrinsic compression of the celiac artery. Although the concept of extrinsic compression of vessels is well established in vascular surgery, the existence of the celiac artery compression syndrome has been a matter of controversy. A patient relieved of celiac artery compression and postprandial pain is presented. A review of the controversy and an approach to evaluating patients suspected of having this type of compression is outlined. [ABSTRACT FROM AUTHOR]

Although the mechanisms underlying ischemia/reperfusion injury remain elusive, evidence supports the etiologic role of intracellular calcium overload and oxidative stress induced by reactive oxygen species. Activation of the sodium hydrogen exchanger (NHE) is associated with intracellular calcium accumulation. Inhibition of the NHE-1 isoform may attenuate the consequences of this injury. Although there is strong preclinical and early clinical evidence that NHE inhibitors may be cardioprotective, definitive proof of this concept in humans awaits the results of ongoing clinical trials. [Copyright &y& Elsevier]

Studies the beneficial effects of adenosine A[sub 2a] agonist CGS-21680 in infarcted and stunned porcine myocardium. Regional ventricular function and load-insensitive contractility; region at risk and infarct size in the infarction protocol; Systemic hemodynamics and coronary blood flow during myocardial stunning.