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Objective: To study the effects of resveratrol (Res) on pyroptosis of colorectal cancer cells . Methods: ①The experiment of dextran sodium sulfate (DSS) induced colon cancer (CRC) in mice: 30 C57BL/6 mice were randomly divided into control group, Azoxymethane (AOM) group, AOM/DSS group, AOM/DSS+Res group and Res group, with 6 mice in each group, the modeling cycle was 70 days in total. Mice in AOM group, AOM/DSS group and AOM/DSS+Res group, at the first day of the first week, were intraperitoneally injected with AOM (10 mg/kg) once, and the ordinary chaw was replaced with high iron feed, and sterile water was given, 1% DSS water was given to AOM/DSS group and AOM/DSS+Res group. The mice in AOM/DSS+Res and Res groups were given resveratrol (50 mg/kg) by oral gavage, When the mold was finished, colon tissue of mice was fixed, embedded and sectionalized. The expressions of NLRP3, Caspase-1 and IL-18 in colon tissues of mice were detected by IHC and Western blot. ②In vitro experiment: HCT 116 cells were given Res (2.4 μg/L) and transfected with miR-31. The Res was divided into 4 groups and labeled with 0 h, 12 h, 24 h and 48 h respectively. The transfected cells were divided into 5 groups: Control group, miR-31 mimic group, miR-31 mimic + Res group, miR-31 inhibitor group, miR-31 inhibitor + Res group. The protein expressions of NLRP3, Caspase-1, GSDMD-N, IL-18 and IL-1β were detected by Western blot. Results: Animal experiments: Compared with control group, the protein expressions of NLRP3, Caspase-1 and IL-18 in AOM/DSS group were increased significantly (P<0.01). The protein expression levels of NLRP3, Caspase-1 and IL-18 in AOM/DSS+Res group were significantly lower than those in AOM/DSS group (P<0.01). Cell experiments: Compared with the control group, the protein expressions of NLRP3 (P<0.01), GSDMD-N (P<0.05) and IL-18 (P< 0.01) in miR-31 mimic group were increased significantly. The protein expressions of NLRP3, GSDMD-N and IL-18 in miR-31 inhibitor group were decreased significantly (P<0.05). Conclusion: Res inhibited the pyroptosis of colorectal cancer cells through pyroptosis.

Objective: To investigate the effects of miR-31 on TLR4/NF-κB signaling pathway and apoptosis-related proteins in dextran sulfate sodium (DSS) induced mouse colon colitis. Methods: ① Mouse model of colon colitis: 1% DSS was used to induce mouse ulcerative colitis (UC). Fourteen FVB non-transgenic mice were randomly divided into control group (n= 6), DSS group (n= 8), and 16 FVB miR-31 transgenic mice were randomly divided into miR-31 overexpression group (n= 8), miR-31 overexpression +DSS group (n= 8). DSS was dissolved in water and administered to mice by drinking water. The DSS group and miR-31+DSS group drank 1% DSS water in the first week, normal sterilized water in the second week, and 1% DSS water in the third week, after 5 weeks, the modeling was completed, then the colon tissues of the mice were collected. Western blot and IHC were used to detect the expressions of NF-κB p65, TLR4, Bax and Bcl-2 proteins in mouse colon tissue, TUNEL was used to detect apoptosis of mouse colon tissues. ② Cell culture experiments: Transfection of miR-31mimic and inhibitor by lipofectamine resulted in overexpression or knockdown of miR-31 in human colon epithelial cell line HCT 116 cells, each group was repeated three times and cells were collected 48 h later, Western blot was used to detect the expressions of NF-κB p65 and TLR4 protein. Results: ① In animal experiments, compared with the control group, the expression levels of NF-κB p65, TLR4 protein and apoptotic cell index in the DSS group and miR-31 overexpression group in mouse colon tissue were significantly increased (P＜0.05 or P＜0.01), and the Bcl-2 / Bax ratio was significantly reduced (P＜0.05 or P＜0.01); and compared with the DSS group, the expression levels of NF-κB p65, TLR4 protein and apoptotic cell index in the miR-31+DSS group were significantly increased (P＜0.01), while the Bcl-2/Bax ratio was significantly decreased (P＜0.01). ② In cell experiments, compared with the control group, the expression levels of NF-κB p65 and TLR4 protein in the over-expressed miR-31 group of HCT 116 cells were significantly increased (P＜0.05 or P＜0.01), the expressions of NF-κB p65 and TLR4 protein in miR-31 knockdown group were decreased (P＜0.05). Conclusion: miR-31 promotes the development of colitis by promoting TLR4/NF-κB signaling pathway and mediating apoptosis of intestinal epithelial cells.

Objective: To investigate the protective effects of nitidine chloride (NC) on dextran sodium sulfate (DSS) - induced ulcerative colitis (UC) in mice by targeting miR-31 and its underlying mechanisms., Methods: DSS at the concentration of 1% was used to induce UC in mice. Thirty C57BL/6 male mice were randomly divided into four groups: normal control group (n=7), DSS group (n=8), DSS + NC group (7.27 mg/kg) (n=8) and NC group (n=7). DSS was added in drinking water, and NC was administrated by gavage. The period of modeling lasted for 3 weeks. The control group and NC group drank sterile water every day, DSS group and DSS + NC group drank 1% DSS water in the first week, normal water in the second week and 1% DSS water in the third week. In the last week of modeling, mice in control group and DSS group were given 0.5% CMC-Na by gavage, while mice in DSS + NC group and NC group were given NC by gavage. After the establishment of the model, the disease activity index (DAI) related to colitis was observed, the pathological score of colon tissue was evaluated by HE staining, the expression level of miR-31 in colon tissue was detected by qPCR, and the protein expressions of NF -κ B and COX-2 in colon tissue were detected by Western blot., Results: ① Compared with DSS group, the DAI in the DSS + NC group was decreased (P＜0.01). The colonic pathological injury was obviously ameliorated after treated by NC. ② Compared with normal control group, the expression of miR-31 in colonic tissue of DSS group was increased significantly(P＜0.01), compared with DSS group, the expression of miR-31 was decreased after treatment with NC(P＜ 0.05). ③ Compared with DSS group, the levels of inflammatory protein NF-κB and COX-2 in DSS + NC group was decreased significantly (P＜0.05)., Conclusion: Nitidine chloride has obvious therapeutic effects on DSS induced mouse colitis, and its anti-inflammatory mechanism is related to the down-regulation of miR-31 expression.

Objective: To investigate the anti-ulcerative colitis mechanism of resveratrol through regulation of Wnt/β-catenin signaling pathway., Methods: ①The experiment of ulcerative colitis induced by dextran sulfate sodium salt (DSS): 28 C57BL/6 mice were randomly divided into four groups including control group(n=7), DSS group(n=7), DSS+Resveratrol (DSS+Res) group(n=7) and Res group(n=7). The experiment lasted for 3 weeks. Ulcerative colitis of mice was induced by drinking DSS water and treated with resveratrol by intragastric administration. The mice were weighed daily and their activities and state of feces were recorded. After that, the mice were euthanized, the spleens were weighed, and the colonic length was measured.Hematoxylin-eosin staining (HE) was used to observe the pathological changes of the colon, and the expression of miR-31 in colonic tissue was detected by quantitative real-time PCR (qPCR). The expressions of β-catenin and Cyclin D1 were measured by Western blot. ②In vitro experiment: HCT 116 cells were treated with resveratrol at 10 mg/ml, the expressions of β-catenin, LDL receptor related protein-6 (LRP-6), frizzled-3 (FZD3) and c-Myc were detected. The expression of β-catenin was also detected in HCT 116 cells transfected with miRNA-31 mimic and miRNA-31 inhibitor., Results: ① The body weight was decreased in DSS group, the activity was decreased and blood stool appeared. The colonic length of mice was shortened, the spleen was enlarged and the tissue was damaged seriously in DSS group. While the above symptoms were improved after resveratrol treatment. ② Resveratrol inhibited the expressions of miRNA-31, β-catenin and CyclinD1 in ulcerative colitis mice, and also down-regulated the expressions of β-catenin, LRP-6, FZD3 and c-Myc in HCT 116 cells. After transfection of miRNA-31 inhibitor, the expression of β-catenin was decreased in HCT 116 cells., Conclusion: Resveratrol suppresses DSS induced colitis by down-regulation of Wnt signal pathway. The down-regulation of Wnt signal may be related to miRNA-31.

Objective: To investigate the protective effects and the possible mechanisms of simvastatin on myocardial injury induced by diabetes., Methods: Twenty-four SD rats (180~220)g were randomly divided into control group (control, n =8) and modeled groups( n =16), the modeled groups were injected with streptozotocin intraperitoneally to induce diabetes. Then the modeled rats were randomly divided into diabetes mellitus group (DM group, n =8) and diabetes mellitus + simvastatin group (DM+S group, n =8). Rats in DM+S group were treated with simvastatin at the dose of 40 mg/(kg·d)by gavage for 4 weeks, and the other two groups were treated with the same amount of saline. At the end of experiments, the heart tissues were collected for further observation. The content of malondialdehyde (MDA) and the activity of superoxide dismutase (SOD) in heart tissues were measured by spectrophotometry; HE staining of rat heart slides was used to observe the pathological changes; TUNEL assay was used to determine the apoptosis index of myocardial cells in each groups; The distribution of p53 in the heart tissues was evaluated by immunohistochemistry; Western blot was used to detect the expressions of p53, p53-phospho-serine 15, Bax and Bcl-2 in the heart tissues., Results: ①Compared with control group, the content of malondialdehyde (MDA) was increased while the activity of superoxide dismutase (SOD) was decreased significantly in DM group ( P <0.01). After simvastatin administration, the activity of SOD was increased and the content of MDA was decreased significantly ( P <0.01). ② HE staining results showed that the myocardial cells in the DM group were disorganized, with unclear morphological structure and a large number of inflammatory cells infiltration. Compared with DM group, the myocardial morphology in DM+S group was improved significantly. ③TUNEL staining results showed that the apoptosis index of myocardial cells in DM group was increased significantly compared with that of control group, and the apoptosis index was decreased significantly after the treatment of simvastatin ( P <0.01).④ Immunohistochemistry showed that compared with control group,the expression of p53 in DM group was increased significantly, and was expressed in both cytoplasm and nucleus, while the expression of p53 in DM+S group was decreased and the expression of p53 in nucleus was decreased significantly ( P <0.01). ⑤ The results of Western blot showed that the expression levels of p53, p53-phospho-serine15 and Bax were higher than those in control group, and the expression of Bcl-2 was lower than that in control group ( P <0.01). After simvastatin administration, the expression levels of p53,p53-phospho-serine 15 ( P <0.01) and Bax were decreased significantly ( P <0.05) and the expression of Bcl-2 was increased ( P <0.05)., Conclusions: Simvastatin exerted protective effects on myocardial injury caused by diabetes through improving the abnormal morphological changes of diabetic myocardium, alleviating oxidative stress and inhibiting apoptosis of myocardial cells. The mechanism is related to the regulation of apoptosis pathway mediated by p53.

Objective: To observe the protective effect of simvastatin on renal injury in diabetic rats and to explore the possible molecular mechanism., Methods: Twenty-four SD rats were randomly divided into normal control (NC) group ( n =8) and modeling group ( n =16).The rats in modeling group were injected with streptozotocin intraperitoneally at a dose of 55 mg/kg to establishing diabetic rat model. After diabetic ratmodel established successfully, the diabetic rats were randomly subdivided into diabetes mellitus (DM) group and diabetes mellitus + simvastatin (DM+Sim) group ( n =8).Rats in DM+Sim group were given simvastatin at a dose of 40 mg/kg by oral gavages, once a day for 4 weeks. Morphological changes and interstitial fibrosis of kidney were observed by histopathological method. The expressions of relative protein in endoplasmic reticulum stress, inflammatory molecules in renal tissues and cells apoptosis were detected by molecular biology method., Results: ① Compared with NC group, the pathological changes of glomerulus and tubulointerstitium were obvious, and the collagen fibers were obviously erythrophilous and unevenly distributed in DM group. Compared with DM group, the morphological changes and fibrosis were significantly improved in DM+Sim group. ② The expressions of GRP78, p-IRE1α, NF-κB p65 and MCP-1 in DM group were significantly higher than those in NC group ( P <0.05), while the expressions of GRP78, p-IRE1α, NF-κB p65 and MCP-1in DM + Sim group were decreased ( P <0.05). ③ There were a small number of apoptotic nuclei in the glomeruli and adjunctive renal tubules in NC group detected by TUNEL assay, while there were a large number of apoptotic nuclei in DM group ( P <0.01). The number of apoptotic nuclei was decreased significantly in DM+Sim group ( P <0.01)., Conclusions: Morphologicalchanges and fibrosis of renal tissue are improved obviously, and the number of apoptotic cells is decreased significantly after administration of simvastatin in diabetic rats. Simvastatin exertsthe protective effect on diabetic nephropathy by inhibiting endoplasmic reticulum stress and NF-κB inflammatory signaling pathway, and reducing renal cell apoptosis.

Objective: To investigate the effects of β3-adrenoceptors(β3-AR) inhibitor SR 59230A on MicroRNAs expression in rat myocardium with chronic heart failure and the related mechanisms., Methods: One hundred male SD rats were randomly divided into sham operated group(40)and chronic heart failure(CHF)group(60). Coronary artery ligation was used to induce CHF. Then the rats in CHF group were further randomly divided into CHF control group and CHF+SR 59230A group (CHF+SR). Rats in the sham group were divided into sham control group and sham+SR 59230A group (Sham+SR). The rats in Sham+SR group and CHF+SR group were treated with 1 ml SR 59230A(85 mmoL/L in 0.9% saline)twice a day for seven weeks by intraperitoneal injection, while the rats in control groups were injected with the same amount of saline for seven weeks separately. miScript miRNA PCR Arrays were used to determine the expression profile of MicroRNAs. Immunohistochemistry was used to evaluate the distribution of the related proteins in the heart tissue sections. Western blot was used to detect the expressions of nuclear factor-kappaB(NF-κB),p53 and p53-Phospho-Serine 15 in the heart., Results: ①After in vivo blockade of β3-AR by SR 59230A, there were 18MicroRNAs down-regulated in sham control group and CHF control group. Within them, 6 MicroRNAs were related to NF-κB signaling pathway, they were miR-125b-5p,miR-143-3p,miR-145-5p,miR-26a-5p,miR-30a-5p and miR-320-5p. ②Slides from the heart tissue showed that NF-κB was distributed both in nucleus and cytoplasm, while p53 in cytoplasm was more than that in nucleus in heart tissue sections. The expressions of NF-κB and p53 were higher in the CHF control group than those in the sham control group( P <0.05), but were lower in CHF+SR group than those in CHF control group( P <0.05),while they were elevated in Sham+SR group compared to the sham control group( P <0.05). ③ Compared with the sham control group, the protein expression of NF-κB p65 was increased significantly in the CHF control group ( P <0.05). After treated with SR59230A in vivo ,the protein expressions of NF-κB and p53-Phospho-Serine 15 were decreased significantly in CHF rats( P <0.05),while the protein expressions of NF-κB, p53 and p53-Phospho-Serine 15 proteins were increased in the sham rats ( P <0.05)., Conclusions: Blocking of β3-AR improved the damaged heart in CHF rats; β3-AR caused the change of MicroRNAs expression, and it related to NF-κB signal pathway.

Objective: To explore whether targeting phosphoglycerate kinase 1 (PGK1) can enhance the sensitivity of BRAF V600E mutation melanoma cells to vemurafenib., Methods: The methods of cell biology, molecular biology and pharmacology(MTT assay, Western blot, FCM, Colongenic assay) were used in this study., Results: ① Silencing of PGK1 expression increased the efficacy of vemurafenib in melanoma cells, as evidenced by greater killing in the tumor cells subjected to combined treatment of vemurafenib with siPGK1; ②The mechanism of enhanced sensitivity of melanoma cells to vemurafenib was associated with activation of apoptotic signaling pathway., Conclusions: Targeting of PGK1 may represent a novel strategy of sensitizing melanoma cells to vemurafinib.

Objective: To explore the effects of SR59230A on the tension and microRNA (miRNA) expression of rat thoracic aorta., Methods: Forty-four SD rats were used in the experiment. Twenty-four rats were used to observe the effect of SR on the tension of thoracic aortic rings. Another 20 rats were randomly divided into control ( n =10) and SR group( n =10). Rats in SR group were injected SR intraperitoneally,and in control group were given 0.9% of saline. After 5 weeks, the blood pressure of all rats were measured. Then the tension to NA and the expression of miRNA of thoracic aorta rings were measured., Results: (1) The tension of thoracic aortic rings responding to 30 mmol/LKCl were increased by pretreatment of SR ( P <0.05); (2) After 5 weeks injection of SR, systolic pressure was increased ( P <0.05); (3) The tension in SR group was increased in presence of 1 μ mol/L and 10 μ mol/L of NA ( P <0.05, P <0.01). (4) After 5 weeks of SR in vivo application,18 miRNA were down-regulated, 7 of them had statistical significance, they were rno-miR-143-3p, rno-miR-29b-3p, rno-miR-31a-5p, rno-let-7b-5p, rno-miR-214-3p, rno-miR-222-3p and rno-miR-352; 11 miRNA were up-regulated, 4 of them had statistical significance, they were rno-miR-206-3p、rno-miR-223-3p、rno-miR-342-3p and rno-miR-499-5p respectively., Conclusions: SR59230A increased the tension of rat thoracic aorta. In vivo administration of SR led to increase of systolic pressure of rat,down-regulation of rno-miR-143-3p、rno-miR-29b-3p、rno-miR-31a-5p、rno-let-7b-5p、rno-miR-214-3p、rno-miR-222-3p、rno-miR-352 and up-regulation of rno-miR-206-3p、rno-miR-223-3p、rno-miR-342-3p and rno-miR-499-5p.

Objective: To observe the effect of β₃adrenoceptors (β₃-AR) activation on rat thoracic aorta smooth muscle contractility and the possible related mechanism., Methods: The endothelium removed thoracic aorta was pre-contracted with 30 mmol/L KCl physiological saline solution (PSS). Then the tension of the thoracic aorta was recorded in presence of BRL37344 (BRL) to determine the action of β₃-AR. The tension of the thoracic aorta was also recorded in the presence of Propranolol (PRA), SR59230A (SR), L-NNA, H-89 and Iberiotoxin (IBTX) respectively to reveal the underling mechanism of β₃-AR activation on rat vascular smooth muscle. Immunohistochemistry was adopted to confirm the existence and the distribution of β₃-AR in rat thoracic aorta., Results: The results showed that: (1) The thoracic aorta was relaxed by β₃-AR activation, with a relaxation percentage of (10.59 ± 0.79). (2) β₃-AR was expressed in both endothelial and smooth muscle layer in thoracic aorta sections of rats. (3) PRA did not block the effect of BRL on the thoracic aorta. The relaxation actions of BRL could be antagonized by pre-incubating the thoracic aorta with SR. (4) L-NNA (a NOS inhibitor) and H-89 (a PKA inhibitor) reversed the relaxation effect of BRL on vascular smooth muscle. (5) The effect of BRL was decreased after application of Ibriotoxin (IBTX), a large conductance calcium dependent potassium channel blocker., Conclusion: The results confirmed that activation of β₃-AR led to relaxation of thoracic aorta smooth muscle. The relaxation action of β₃-AR on smooth muscle of rat thoracic aorta was related to activation of NOS and PKA signaling pathway. Large conductance Ca²⁺-K⁺ channels were involved in the relaxation action of β₃-AR activation on rat thoracic aorta smooth muscle.

Objective: To analyze the features of isocitrate dehydrogenase 1 (IDH 1) mutation in 165 oligodendroglial tumors., Methods: IDH1 was detected in a series of 165 oligodendroglial paraffin specimens from 2009 to 2011. And their features were analyzed., Results: Mutant IDH1 was detected in 111 (67.3%) tumors including 109 (98.2%) CGT→CAT mutations, 1 (0.9%) CGT→AGT mutation and 1 (0.9%) CGT→TGT mutation. The frequencies of IDH mutation in AO, O and OA were 13/15, 83.3% and 72.9% respectively. They were significantly higher than that in AOA (27.0%, P < 0.001)., Conclusion: The different frequencies of IDH1 mutation in different subsets of oligodendroglial tumors may imply varied tumorigenic pathways between subsets.

Objective: To investigate the frequencies of combining loss of heterozygosity (LOH) of chromosome 1p/19q in gliomas of different pathologies and analyze the clinical factors correlated with combining LOH by logistic regression., Methods: Tumor samples from 127 glioma patients were collected. The status of 1p and 19q was evaluated by fluorescence in situ hybridization (FISH) and the frequencies of combining 1p/19q LOH in gliomas of different pathologies were analyzed., Results: The frequencies of combining 1p/19q LOH in astrocytic, oligoastrocytic and oligodendroglial tumors were 19.30%, 50.00% and 80.77% respectively. The frequencies of combining 1p/19q LOH in oligoastrocytic and oligodendroglial tumors were higher than those in astrocytic tumors (P < 0.01) and the frequencies of combining 1p/19q LOH in oligodendroglial tumors was higher than those in oligoastrocytic tumors (P < 0.05). The frequencies of 1p/19q LOH in astrocytic, oligoastrocytic and oligodendroglial tumors were 12.28%, 11.36 and 0 respectively. There was no significant correlation between combining 1p/19q LOH and age, gender and grade by logistic regression., Conclusion: In gliomas, combining 1p/19q LOH is proved to be the most common pattern of chromosome deletion involving 1p or 19q. It is significantly correlated with oligodendroglial component. Combining 1p/19q LOH may be valuable in the diagnosis, treatment and prognostic prediction for glioma with oligodendroglial component.

Objectives: To find possible factors correlated with combined loss of heterozygosity (LOH) of 1p and 19q., Methods: The status of 1p and 19q of 138 glioma specimen from January 2009 to December 2009 was evaluated by Fluorescence in situ hybridization (FISH) method, and the frequencies of combining LOH of 1p/19q were compared between different pathologies, brain sub-regions, genders and ages., Results: The frequencies of combined LOH of 1p and 19q of oligodendroglial (81.3%) and oligo astrocytic tumors (55.8%) were significantly higher than that of astrocytic tumor (22.2%) (P < 0.01), and the frequency of oligodendroglial tumor was significantly higher than that of oligo astrocytic tumor (P < 0.05). The frequency of combining LOH of 1p and 19q in frontal lobe (61.8%) was higher than that in temporal (31.8%) and insular lobes (34.6%) (P < 0.05)., Conclusion: Combining LOH of 1p and 19q has significant correlation with the pathologies and brain sub-regions.

Neuropeptide Y (NPY) co-exists with norepinephrine (NE) in sympathetic terminals, and is the most abundant neuropeptide in myocardium. Many studies have focused on the effects of NE on ion channels in cardiac myocytes and its physiological significance has been elucidated relatively profoundly. There have been few investigations, however, on the physiological significance of NPY in myocardium. The effects of NPY on L-type Ca2+ channel currents (I(Ca-L)) were evaluated in some studies and different results were presented, which might be attributed to the different species of animal tested and different methods used. It is necessary, therefore, to study the effects of NPY on ion channels in cardiac myocytes systematically and further to discuss the biological significance of their coexistence with NE in sympathetic terminals. The single ventricular myocytes from adult rat or guinea pig (only for measuring I(K)) were prepared using enzymatic dispersion. I(Ca-L), I(to), I(Na/Ca), I(Na) and I(K) in the cellular membrane were observed using whole cell voltage-clamp recording. In the present study, NPY from 1.0 to 100 nmol/L dose-dependently inhibited I(Ca-L) (P<0.01, n=5). The maximal rate of inhibition in this study reached 39% and IC(50) was 1.86 nmol/L. NPY had no effect on the voltage-dependence of calcium current amplitude and on the voltage-dependence of the steady-state gating variables. I(Ca-L) was activated at -30 mV, reaching the maximum at 0 mV. When both NE and NPY were applied with a concentration ratio of 500:1, 10 nmol/L NPY inhibited I(Ca-L) that had been increased by 5 mumol/L NE, which was consistent with the effect of NPY only on I(Ca-L). NPY also inhibited I(Na/Ca). At a concentration of 10 nmol/L, NPY inhibited inward and outward I(Na/Ca) from (0.27+/-0.11) pA/pF and (0.45+/-0.12) pA/pF to (0.06+/-0.01) pA/pF and (0.27+/-0.09) pA/pF, respectively (P<0.05, n=4). NPY at 10 nmol/L increased I(to) from (12.5+/-0.70) pA/pF to (14.7+/-0.59) pA/pF(P<0.05, n=4). NPY at 10 nmol/L did not affect I(Na) in rat myocytes and I(K) in guinea pig myocytes. NPY increased the speed of action potential depolarization and reduced action potential duration of I(Ca-L), I(Na/Ca) and I(to), which contributed to the reduction of contraction. These results indicate that the effects of NPY are opposite to the effects of NE on ion channels of cardiac myocytes.