针刺手厥阴心包经穴对心肌缺血再灌注损伤心肌细胞钙超载的影响

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心肌细胞钙超载的影响。方法:实验分空白组、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。电针大鼠心包经穴位20 min后,结扎左冠状动脉前降支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,取心室肌制成心肌细胞悬液,细胞浓度为106个/mL,用DMSO溶解荧光染料,Fluo-3负载,激光扫描共聚焦显微镜下观察Ca2+的变化。结果:模型组细胞内Ca2+含量明显增高,荧光分布多,强度高。针刺心包经穴组与模型组比较差异均有显著性(P<0.01)。结论:针刺手厥阴经穴能有效地抑制心肌细胞的钙超载,减轻损伤的程度,起到保护心肌的作用。

Effect of Electroacupuncture of Acupoints of the Pericardium Meridian on Intracellular Calcium Overload in Myocardial Ischemia/ Reperfusion Injury Rats

Objective: To explore the effect of electroacupuncture(EA) of acupoints of the Pericardium Meridian of Hand-Jueyin on intracellular calcium overload in myocardial ischemia/reperfusion(IR) injury rats.Methods: Forty Wistar rats were evenly randomized into control,model,EA-"Neiguan"(PC 6),EA-"Ximen"(PC 5) and EA-"Zhigou"(TE 6) groups.Myocardial IR model was established by occlusion of the left descending anterior branch of the coronary artery for 40 min,followed by reperfusion for 60 min.EA(frequency 30-100 Hz,strength 20-22 V,dense-sparse waves) was applied to the abovementioned acupoints for 20 min.Then,myocardial tissue sample(below the ligation site) of the left cardiac ventricle was taken to be processed into cell suspension,followed by adding fluorescence indicator dye(Fluo-3/AM,for labeling Ca~(2+)) and assaying the concentration of calcium ions in the myocardial cells by using laser scanning confocal microscope.Results: The fluorescence intensity of the labeled intracellular Ca~(2+) in control,model,EA-PC-6,EA-PC-5 and EA-TE-6 groups were 67±17,105±32,70±14,73±29 and 99±15 respectively,showing that after myocardial IR,intracellular Ca~(2+) concentration increased significantly,after EA of "Neiguan"(PC 6) and "Ximen"(PC 5) of the Pericardium Meridian,it lowered obviously(P<0.05,0.01).No significant differences were found between EA-PC-5 and EA-PC-6 groups,and between EA-TE-6 and model groups(P>0.05).Conclusion: EA stimulation of acupoints of the Pericardium Meridian can effectively inhibit intracellular Ca~(2+) overload caused by myocardial IR injury,which may contribute to the effect of acupuncture in reducing myocardial injury and protecting myocardial performance.