电针内关穴预处理对大鼠心肌缺血再灌注后线粒体功能及超微结构的保护作用

Effects of electroacupuncture preconditioning at Neiguan(PC6) on the myocardial mitochondrial function in rats with myocardial ischemia-reperfusion injury

目的:探讨电针内关穴预处理对心肌缺血再灌注损伤过程中心肌线粒体的保护作用。方法:选用3月龄Wistar雄性大鼠30只,体质量(220±28)g,编号后按随机数字表分入空白组、模型组、电针预处理组,每组10只。造模采用结扎左冠状动脉前降支,缺血30min,再灌注2h,随即处死大鼠,留取左心室心肌组织,采用黄嘌呤氧化法检测心肌超氧化物歧化酶(SOD)活性,硫代巴比妥酸法检测心肌丙二醛(MDA),通过极谱法检测系统测定线粒体呼吸控制率(RCR),透射电镜下观察心肌超微组织的变化。结果:电针预处理组大鼠部分心肌肌丝溶解、断裂,心肌细胞轻微肿胀,轻度空化,线粒体排列稍紊乱,部分线粒体水肿、存在空泡样病变。电针预处理组的大鼠线粒体RCR、SOD及ATP含量明显高于模型组(P<0.01),MDA含量明显低于模型组(P<0.01)。结论:电针内关穴预处理能改善心肌组织形态学表达,防止心肌组织结构的破坏,修护心肌缺血性损伤,更对线粒体的结构与功能起到了良性的保护作用。

Objective: To explore the protective effects of electroacupuncture preconditioning at Neiguan(PC6) on myocardial cells in the process of myocardial ischemia and trperfusion injury. Methods: Thirty male Wistar rats, 3-month-old, weighting about(220±28)g, were randomly divided into three groups: the no-treatment control(sham operation) group(NC group), the myocardial ischemia-reperfusion injury model group(M group) and the electroacupuncture preconditioning group(EA group), with 10 rats in each group respectively. Ischemia-reperfusion injury model was established by the ligation and deligation of left anterior descending artery with ischemia for 30 min and reperfusion for 120 min. Then rats were sacrificed immediately and the left ventricular myocardium tissues were taken. The activity of superoxide dismutase(SOD) in myocardium was measured by xanthine oxidase method. Malondialdehyde(MDA) in myocardium was measured by thiobarbituric acid method. Mitochondrial respiratory control rate(RCR) was measured by a polarographic system. The ultrastructural changes of myocardium were observed by transmission electron microscope. Results: In the group EA, the myocardial filaments of rats were dissolved and broken, the myocardial cells were slightly swollen, mild cavitation, mitochondria arranged slightly disordered. Some of the mitochondria were edematous and vacuolated. The mitochondrial RCR of rats in group EA was normal, higher than that in M group significantly(P<0.01). However, the mitochondrial RCR in group EA was significantly lower than that in NC group(P<0.01). Conclusion: Electroacupuncture preconditioning at Neiguan(PC6) could improve the morphological expression of myocardial tissue, prevent the destruction of myocardial tissue structure, repair myocardial ischemic injury, and play a benign protective role on the structure and function of mitochondria.