中文摘要：

目的：研究酸枣仁皂苷A预处理对过氧化氢诱导心肌细胞凋亡、胞浆细胞色素C（CytC）表达及Caspase-3活性的影响。方法：采用差速贴壁法体外分离培养新生乳鼠心肌细胞,以500μmol/L过氧化氢作用4小时建立心肌细胞氧化损伤模型,以酸枣仁皂苷A（20 mg/L）在造模前干预24小时。倒置显微镜观察心肌细胞形态学变化;四唑盐（MTT）比色法检测心肌细胞活力;流式细胞仪检测细胞凋亡率;采用蛋白印迹法检测胞浆CytC表达,分光光度法检测caspase-3的活性。结果：模型组经500μmol/L过氧化氢作用4小时后,细胞核暗淡,伪足显著变细,细胞间连接明显减少,搏动节律明显减慢,细胞活力显著下降（P〈0.01）,细胞凋亡率显著增高（P〈0.01）。与模型组比较,酸枣仁皂苷A能显著改善心肌细胞形态、提高细胞活力及显著降低细胞凋亡率（P〈0.01）。模型组中胞浆CytC表达及caspase-3活性显著升高（P〈0.01）。与模型组比较,酸枣仁皂苷A组的胞浆CytC表达及caspase-3活性显著下降（P〈0.01）。结论：酸枣仁皂苷A可明显抑制过氧化氢诱导的心肌细胞凋亡,其机制可能与下调胞浆中CytC蛋白表达及caspase-3活性有关。

英文摘要：

Objective： To investigate the effects of jujuboside A preconditioning on the expression of Cytochrome C in the cytoplasm, the activity of caspase-3 and the apoptosis of myocardial cell induced by hydrogen peroxide in rat. Method： Myocardial cell of neonate rat was cultured with differential adhesion method and preconditioned with jujuboside A （20 mg/L） for one day before setting up the models, and then they were established in the medium of 5001.1 mol/L hydrogen peroxide for four hours. Morphologic changes of myocardial cells were observed under the inverted microscope; the activity of myocardial cells was tested with MTT; the expressions of Cytochrome C in the cytoplasm were tested with Western blotting, the activity of caspase-3 was detected with chromatometry. Result： The model group was dealt with 500μ mol/L for four hours, the nucleus darkened, the pseudopodia became thin significantly, the connections among cells lessened obviously, the rhythm of cell beating was decreased remarkably and cellular activity was lowered obviously （P〈0.01）, cellular apoptosis rate was raised significantly （P〈0,01）. Compared with the model group, jujuboside A could significantly improve the morphology of myocardial cells and cellular activity, decrease cellular apoptosis rate （P〈0.01）. The expressions of Cytochrome C in the cytoplasm and the activity of caspase-3 in the model group were raised significantly （P〈0.01）. Compared with the model group, both were decreased obviously （P〈0.01）. Conclusion： Jujuboside A could inhibit myocardial cell apoptosis induced by hydrogen peroxide, the mechanism might be related to the expressions of Cytochrome C in the cytoplasm and the activity of caspase-3.