温阳益心中药对梗死大鼠心肌超微结构的影响

Effects of TCM Preconditioning of Warming Yang and Supplementing Heart Qi on Myocardial Ultrastructure of Rats with Acute Myocardial Ischemia

目的观察温阳益心中药对梗死大鼠心肌超微结构的影响,探讨其对心肌缺血-再灌注(IR)大鼠心肌的保护作用及其与心肌缺血预适应(IP)保护机制的关联性。方法选用雄性Wistar大鼠,随机分为4组,其中3组正常喂食,1组灌胃中药悬液,10d后建立大鼠心肌缺血模型。IR组:心肌缺血45min,再灌注48h。温阳益心中药预处理缺血-再灌注组(中药组):每日灌胃温阳益心中药悬液0.36g/100g,连续10d;心肌缺血45min,再灌注48h。预适应处理缺血-再灌注组(IP组):心肌缺血5min,再灌注5min,重复3次,然后心肌缺血45min,再灌注48h。采用电镜技术观察各组大鼠心室心肌超微结构改变。结果IR组肌膜破损,肌丝溶解断裂,排列松散,线粒体排列紊乱,有的线粒体呈空化或局部空化状,有的呈凝聚状,糖原减少。心肌损害较重,证实心肌缺血-再灌注后部分心肌坏死。中药组、IP组心肌细胞状态有所改善,肌膜完整,心肌细胞核呈椭圆形,核仁明显,线粒体较为明显,肌丝排列较为整齐,肌节明暗带清晰可见,线粒体较为整齐地排列在肌原纤维之间,但仍可见有些肌丝断裂及个别线粒体部分空化。结论心肌缺血预适应和温阳益心中药预处理可以通过减轻心肌超微结构损伤而保护缺血心肌,且二者对缺血再灌注大鼠心肌的超微结构损伤保护效应相近。

Objective To observe the effects of TCM preconditioning of warming Yang and supplementing heart Qi on the myocardial ultrastructure of rats with acute myocardial ischemia, and discuss its protection on the ischemia reperfusion myocardium and relation with myocardial ischemic preconditioning. Method Male Wistar rats were randomly divided into 4 groups, 3 of which were fed normally, one of which was administered with TCM, and myocardial infarction model was established after 10 days. IR group were reperfused 48 hours after 45 min of ischemia. TCM group were treated with prophylactic administration of 0.36 g/100 g body weight for 10 days before the same ischemia and reperfusion as IR group. IP group were also performed the same ischemia and reperfusion as IR group after 5 min of ischemia and 5 min of reperfusion three times. The myocardial ultrastructure of rats was observed by electron microscope.Results In IR group： sarcolemma damaged, myofilament dissolved and fragmented, arranged loosely, mitochondria arranged confused, some mitochondria looked like cavitation or partly cavitation, some also presented coacervation state, glycogen decreased. And the myocardium damaged badly, it proved that part of the myocardium damaged after the ischemia reperfusion. In TCM and IP groups： the state of the cardiocytes were improved relatively and the sarcolemmas were integrated, the cardiocytes＇ nucleoli presented to be oval-shape, and the nucleoli looked obviously, the mitochondria were showed relatively obviously, myofilaments were well arranged, the bright and dark bands of the sarcomeres looked apparently, mitochondria arranged in good order between the myofibrils, but still some myofllaments were broke and part of the mitochondria presented cavitation state. Conclusion The myocardial ischemic preconditioning and TCM preconditioning of warming Yang and supplementing heart Qi both can protect the ischemic myocardium through mitigating the damages of the myocardial ultrastructure, and they have the similar protection effects on the damaged myocardial ultrastructure of the rats with ischemia reperfusion.