吡那地尔、美托洛尔、谷氨酰胺、胰岛素单独及联合使用对H9c2心肌细胞缺氧/复氧损伤的保护作用及机制

目的研究吡那地尔(pinacidil,Pin)、美托洛尔(metoprolol,Met)、谷氨酰胺(glutamine,Glu)、胰岛素(insulin,Ins)四药联用对缺氧/复氧(hypoxia/reoxygenation,H/R)所致H9c2心肌细胞损伤的保护作用并探讨其作用机制。方法将培养的H9c2心肌细胞随机分为7组,即①正常对照(Con)组;②H/R组;③Pin组;④Met组;⑤Glu组;⑥Ins组;⑦四药联用(PMGI)组。测定各组H9c2心肌细胞的存活率;收集培养液测定乳酸脱氢酶(lactate dehydrogenase,LDH)活性,超氧化物歧化酶(superoxide dismutase,SOD)活性;Western印迹法检测保护性蛋白热休克蛋白70(heat shock protein 70,HSP70)的表达情况。结果对于H/R损伤的H9c2心肌细胞,四药联用组与药物单用组或H/R组相比能明显提高细胞存活率,保护细胞膜,减少LDH渗漏;增加抗氧化能力,提高SOD含量;增加HSP70的表达。结论联合用药组与药物单用组相比保护作用增强。

Protective Effects and Mechanism of Pinacidil, Metoprolol, Glutamine, Insulin Single and Combination Thearpy on H9c2 Cardiac Myocytes Exposed to Simulated Hypoxia/Reoxygenation

OBJECTIVE To investigate protective effects and mechanism of pinacidil（Pin）, metoprolol（Met）, glutamine （Glu）, insulin（Ins） on H9c2 cardiacmyocytes exposed to simulated hypoxia/reoxygenation（H/R）. METHODS H9c2 cardiacmyocytes were randomly divided into seven groups： （1）control group; （2）H/R group; （3）Pin group; （4）Met group; （5）Glu group; （6）Ins group; （7）Pin ＋ Met ＋ Glu ＋ Ins （PMGI） group. The survival rates of cardiomyocytes were detected. The activity of lactate dehydrogenase （LDH） and superoxide dismutase （SOD） in the culture medium were measured. Western blot was performed to examine expression of heat shock protein 70 （HSP70） in cardiomyocytes respectively. RESULTS The combination therapy of PMGI can protect the H9c2 cardiac cell membrane caused by hypoxia/reoxygenation injury; increase cell survival rate, decrease LDH leakage, protect cardiac cell against H/R injury through elevating T-SOD and Mn-SOD activity, increase the expression of HSP70. CONCLUSION Compared to the individual group, drug combination treatment enhances protective effects.