热休克预处理对大鼠在体MIRI的保护效应

目的 探讨热休克预处理对大鼠在体MIRI的保护效应.方法 健康成年雄性Wistar大鼠30只,随机分三组:SO组、MIRI组、HS组.左冠状动脉结扎法建立MIRI模型.各组经预处理后,动态监测LVSP、±dp/dtmax、LVEDP等血流动力学指标,检测血浆CK-MB、SOD、MDA等生化指标.术毕光镜下观察心肌组织病理变化.结果 与MIRI组比较,HS组复灌末LVEDP水平明显降低(P＜0.05)、LVSP、±dp/dtmax水平升高(P＜0.05)、血浆CK-MB漏出量明显减少(P＜0.05)、血浆MDA水平降低(P＜0.05)、SOD活性升高(P＜0.05).光镜下,HS组心肌纤维排列较整齐,未见细胞间连接点断裂,闰盘少见.结论 热休克预处理对大鼠在体MIRI具有保护作用,其保护机制可能与抗自由基损伤有关.

THE PROTECTIVE EFFECT OF HEAT SHOCK PRECONDITIONING ON ACUTE MYOCARDIAL ISCHEMIA AND REPERFUSION INJURY OF RATS IN VIVO

Objective To explore the protective effects of heat shock preconditioning on MIRI of Rats in vivo.Methods 30 Healthy adult male Wistar rats were randomly divided into 3 groups:sham-operated group(SO),myocardial ischemia reperfusion injury group(MIRI),and heat shock preconditioning group(HS).Establishing the MIRI model by ligating left coronary artery method.After pretreated,the hemodynamic parameters,such as LVSP,±dp/dtmax,LVEDP,etc,were dynamically monitored.The blood SOD,MDA and CK-MB activity were determinated,and the pathological changes of myocardial tissue were observated under the light microscope.Results Compared with MIRI group,the LVEDP were obviously decreased and the LVSP,±dp/dtmax were increased in HS group after irrigation 60 min(P<0.05);The plasma CK-MB level,MDA level were also significantly decreased(P<0.05),SOD activity increased in HS group(P<0.05).The myocardial tissue pathological damage of HS also significantly reduced.Conclusion Heat shock preconditioning had protective effect on MIRI.Its mechanisms might relelated to oxygen radicals resistance.