缺血后适应对大鼠缺血再灌注心肌的保护作用及其与P-Akt的关系

Protective Effect of Myocardial Ischemic Postconditioning on Ischemic-reperfused Myocardium of Rat and Its Relationship with P-Akt

目的探讨缺血后适应对大鼠离体心脏缺血再灌注损伤的影响及其信号机制。方法2周龄健康SD大鼠,体质量250～300g,随机分为空白对照组、缺血再灌注组及缺血后适应组。观测各组大鼠心脏冠状动脉灌注流量、心肌梗死范围,Westernblot检测磷酸化蛋白激酶B(P-Akt)的表达,透射电镜下观察心肌和线粒体的改变。结果缺血后适应组较缺血再灌注组冠状动脉灌注流量明显增加,心肌梗死范围明显减小,P-Akt的表达明显增强,心肌纤维和线粒体的完整程度明显较好。结论缺血后处理在大鼠离体心脏具有显著的保护作用,这一作用可能与Akt激活有关。

Objective To investigate the protective effect of the myocardial ischemic postconditioning on ischemic-reperfused myocardium of rat and its signaling mechanism. Methods Healthy SD rats weighing 250 to 300 g were divided into blank control （N） group,ischemiareperfusion （IR） group and postconditioning （Post） group. We measured heart coronary perfusion flow and myocardial infarct size of the rats in each group. The expression of phosphorylated protein kinase B （P-Akt） was detected by Western blot. The morphological changes of myocardial fibers and mitochondrial were observed under the transmission electron microscopy. Results More coronary flow and less myocardial infarction -were found in Post group than those in IR group. The expression level of P-Akt was higher in Post group. The integrity of myocardial fibers and mitochondrial was better in Post group than IR group. Conclusion Postconditioning had a protective effect for the iscbemic isolated rat heart. Akt activation might play an important role in its mechinism.