针刺手厥阴经穴对心肌缺血再灌注损伤线粒体超微结构的影响

Effects of Electroacupuncture of Acupoints of the Pericardium Meridian on Changes of Myocardial Mitochondria in Myocardial Ischemia and Reperfusion Injury Rats

目的:观察针刺手厥阴经“内关”“郄门”穴在缺血再灌注损伤过程中对线粒体超微结构的影响,阐明电针手厥阴经穴对心肌缺血再灌注损伤的作用机理。方法:Wistar大鼠50只,分为假手术组、缺血再灌注模型组、针刺“内关”治疗组、针刺“郄门”治疗组和针刺“支沟”对照组。在大鼠冠状动脉左前降支根部穿线,电针大鼠穴位20 min后,造模组结扎冠状动脉左前降支40 min,心电图监测,再电针穴位20 min,松扎,恢复灌流60 min,摘取心脏,透射电镜下观察心肌组织线粒体的超微结构变化。结果:缺血再灌注模型组心电图ST段抬高明显,与针刺“内关”及针刺“郄门”治疗组比较差异均有显著性意义(P<0.05),“支沟”组ST段变化趋势与模型组近似,二者比较无显著性差异(P>0.05)。模型组线粒体内室水肿、空泡变,嵴减少,形成较宽的电子透亮区。“内关”及“郄门”治疗组嵴排列整齐,仅见部分线粒体轻度水肿。结论:电针手厥阴经穴可明显减轻线粒体超微结构的病理变化,在一定程度上对缺血再灌注损伤心肌起到了保护作用。

Objective： To explore the effect of electroacupuncture （EA） of acupoints of the Pericardium Meridian of Hand-Jueyin on changes of mitochondria in myocardial ischemia/reperfusion （MI/R） injury rats so as to explore the protective mechanism of acupuncture on ischemic myocardiocytes. Methods： Fifty male Wistar rats anesthetized by 10% urethane （1 g/kg）were evenly randomized into control, model, EA-＂Neiguan＂（PC 6）, EA-＂Ximen＂（PC 5）, EA-＂Zhigou＂（TE 6） groups. Under artificial respiration, MI/R model was established by occlusion of the left descending anterior branch （DAB） of the coronary artery for 40 min, followed by reperfusion for 60 min. EA （30- 100 Hz in frequency, 20-30 V in strength, dense-sparse waves） was applied to the above mentioned acupoints for 20 min, two times altogether. Then, the myocardial sample （below the ligation site of DAB） of the left cardiac ventricle was taken for observing the morphological changes of mitochondria under transmission electron microscope. Results： Before occlusion of DAB, ECG-STⅡ values of the 5 groups had no significant differences （ P〉 0.05）, while after occlusion of the coronary artery, ECG-STⅡ of model and 3 EA groups increased considerably. Compared with model group, ST values of EA-＂Neiguan＂ （PC 6） and EA-＂Ximen＂（PC 5） groups were significantly lower from 20 min to 40 min after occlusion, and 30 min after reperfusion （ P 〈 0.05）, showing that EA could remarkably reduce MI/R induced myocardial injury. Correspondingly, in model group, mitochondrial swelling, reduction in the number of the mitochondrial cristsae, and broken cristae with disordered arrangement and vacuous changes were found, and in EA-＂Zhigou＂（TE 6） group, these pathological changes were similar. But in EA-＂Neiguan＂（PC 6） group, and EA-＂Ximen＂（PC 5） group, the situations were much better. Conclusion： EA stimulation of acupoints of the Pericardium Meridian can improve ischemic ECG and reduce MI/R induced structural injury of myocardial mitochondria in rats, which may contribute to its protective effect on the ischemic myocardial cells.