运动对心肌线粒体钙和细胞色素C的影响

Effect of Exercise on Mitochondrial Calcium Ion and Cytochrome C in Myocardium

目的:研究运动对心肌线粒体钙浓度和细胞色素C含量的影响,以探讨运动对心肌细胞凋亡影响的作用机制。方法:以大鼠中等运动强度训练、一次性力竭运动和过度训练为运动模型,用Daly的方法和微电极电化学法测定大鼠心肌线粒体钙离子的浓度和心肌细胞中细胞色素C的含量,用MDA和SOD试剂盒测试心肌组织中MDA含量和SOD活性。结果:力竭运动和过度训练可造成大鼠心肌线粒体Ca^(2+)浓度、心肌细胞中细胞色素C和MDA含量明显增加,SOD活性显著下降(P<0.01);而中等强度运动训练未见大鼠心肌线粒体Ca^(2+)浓度、心肌细胞色素C、MDA含量和SOD活性的显著变化。结论:力竭运动和过度训练造成的心肌线粒体钙超载而致线粒体损伤,使细胞色素C从线粒体漏入胞浆,是力竭运动和过度训练引起心肌细胞凋亡的机制之一。

Objective A study was made about the effect of exercise on the mitochondrial calcium ion concentration and cytochrome C content in rats. Methods Different exercise models were used such as moderate intensity, one exhaustive exercise, and overload training. Results A significant increase was observed in both mitochondrial calcium ion concentration and cytochrome C and MDA content after overload training and one exhaustive exercise, but no changes were seen after exercise of moderate intensity. The results also indicated that the activities of SOD decreased after overload training and one exhaustive exercise, but not after exercise of moderate intensity. Conclusion The increase of mitochondrial calcium ion concentration in myocardium could cause openings in PT pore of mitochondrial membrane through which the cytochrome C leaked into the cytoplasm. This might be one of the mechanisms of myocardial apoptosis caused by overload training and exhaustive exercise.