基于PI3K/AKT信号通路探讨标本配穴电针对慢性心肌缺血大鼠的保护作用及机制

Exploration on protection and mechanism of electroacupuncture with primarysecondary point association on rats with chronic myocardial ischemia based on PI3K/AKT aignaling pathway

目的:观察标本配穴电针治疗对慢性心肌缺血模型大鼠心肌线粒体超微结构及Bcl-2、Bax蛋白表达影响,探讨标本配穴改善心肌缺血的腧穴配伍效应及实现保护心肌缺血作用的基因调控途径。方法:将经过筛查心电图无异常的70只SPF级Wistar雄性大鼠根据随机数字表法分为正常组、模型组、LY294002组、IGF-1组、内关组、标本配穴组、标本配穴+LY294002组,每组10只,采用盐酸异丙肾上腺素(ISO)注射大鼠腹部皮下的方法制作心肌缺血模型(2mg/kg,共14d);所有针刺组在造模前进行电针针刺预处理,每次10min,电流1m A,波形疏密波,频率2Hz,共治疗21d。治疗后采用电镜观察线粒体超微结构的变化,采用免疫组化技术检测心肌组织中Bcl-2和Bax蛋白表达的变化。结果:与正常组比较,其它各组出现不同程度的心肌线粒体损伤,模型组心肌线粒体损伤明显,LY294002组线粒体损伤最重,各组Bcl-2、Bax蛋白表达增加(P<0.01);标本配穴+LY294002组线粒体损伤及Bcl-2、Bax蛋白表达介于两者之间。与模型组比较,IGF-1组、内关组及标本配穴组心肌线粒体损伤明显改善,而Bcl-2蛋白表达增加(P<0.01),Bax蛋白表达相应减少(P<0.01,P<0.05),并且标本配穴组心肌线粒体损伤改善程度和Bcl-2蛋白表达增加、Bax蛋白表达减少与内关组明显比较差异显著(P<0.01,P<0.05)。结论:标本配穴电针治疗通过PI3K/Akt信号通路可有效调控Bcl-2和Bax蛋白的表达活性,从而起到对慢性心肌缺血大鼠的保护作用。

Objective：To observe the influence of electroacupuncture with primary-secondary point association on mitochondria ultrastructure and expression of Bcl-2 and Bax in myocardium of rats with chronic myocardial ischemia,and explore the curative effect of primary-secondary point association on improving myocardial ischemia and its gene regulation pathway on protecting myocardial ischemia.Methods：Seventy normal male Wistar rats were selected by screening of electrocardiogram and then averagely divided into control group,model group,LY294002 group,IGF-1 group,Neiguan（P6） group,primarysecondary point association group,and primary-secondary point association combined with LY294002 group according to random number table method,10 in each group.Rat models of myocardial ischemia were established by injecting ISO（2mg/kg per day） subcutaneously for 14 days.All the rats in acupuncture groups received pretreatment of electroacupuncture（10min each session,1mA,dilatational wave,2Hz） before modeling for 21 days.After treatment,the changes in ultrastructure of mitochondrion were observed by using electron microscope,and the protein expression of Bcl-2 and Bax in cardiac muscle tissue was tested by suing immunohistochemistry technology.Results：Compared with control group,the mitochondria of rats in the other groups appeared dif ferent degree of damage,and the damage of model group was obvious.The damage of mitochondria of rats in LY294002 group was the most serious,the expression of Bcl-2 and of Bax increased signif icantly（P〈0.01）.The damage of mitochondria and expression of Bcl-2 and Bax of rats in primary-secondary point association combined with LY294002 group might be somewhere in between.Compared with model group,the damage of mitochondria of rats in Neiguan（P6） group,IGF-1 group,and primarysecondary point association group was improved signif icantly,the expression of Bcl-2 increased（P〈0.01）,and Bax decreased accordingly（P〈0.01,P〈0.05）.The damage of mitochondria and expression of Bcl-2 and Bax of rats in IGF-1 group and primarysecondary point association group was improved signif icantly compared with Neiguan（P6） group（P〈0.01,P〈0.05）.Conclusion：Electroacupuncture with primary-secondary point association could ef fectively regulate the expression of Bcl-2 and Bax through PI3K/Akt signal pathway,which play a protective role in chronic myocardial ischemia.