论文部分内容阅读
目的 :探讨缺血预处理 (IPC)对心肌缺血再灌注过程中心肌细胞HSP70mRNA表达的影响。方法 :钳夹犬的左冠状动脉前降支 ,造成心肌缺血再灌注模型 ,应用核酸分子杂交技术观察IPC组与对照组于缺血前及缺血 1h后行再灌注达 1、2、4h的HSP70mRNA表达水平。并在透射电镜下观察两组中再灌注1h心肌组织超微结构的变化。结果 :缺血前IPC组HSP70mRNA水平较对照组明显升高 (P <0 .0 5) ;缺血再灌注达 1h、2h时 ,两组HSP70mRNA水平有继续增高的趋势 ,但IPC组较对照组有显著性差异 (P <0 .0 5) ;再灌注达 4h时 ,两组HSP70mRNA水平均下降 ,并接近对照组缺血前水平 (P >0 .0 5)。电镜观察显示 ,IPC组心肌细胞损伤较对照组明显减轻。IPC能够诱导心肌细胞中HSP70mRNA早期迅速表达 ,并在缺血再灌注的一定时间内呈表达增高的趋势。结论 :HSP70可能作为IPC发挥心肌保护作用的一种介质 ,为进一步开发和利用IPC的心肌保护作用提供理论依据
Objective: To investigate the effect of ischemic preconditioning (IPC) on HSP70mRNA expression in myocardial cells during myocardial ischemia-reperfusion. Methods: The left anterior descending coronary artery was poked and the model of myocardial ischemia / reperfusion was induced in the canine. Using the nucleic acid hybridization technique, the IPC group and the control group were reperfused for 1, 2, 4 h Of HSP70 mRNA expression levels. The ultrastructural changes of myocardial tissue were observed under transmission electron microscope at 1 hour after reperfusion. Results: Compared with the control group, the HSP70 mRNA level in IPC group was significantly higher than that in control group (P <0.05). The HSP70 mRNA level in IPC group was still increased at 1h and 2h after ischemia-reperfusion, (P <0.05). After reperfusion for 4h, the levels of HSP70mRNA decreased in both groups, which were close to those in the control group (P> 0.05). Electron microscopy showed that the damage of cardiomyocytes in IPC group was significantly lower than that in control group. IPC can induce the rapid expression of HSP70mRNA in cardiomyocytes in the early stage, and showed an increasing trend during the period of ischemia-reperfusion. Conclusion: HSP70 may serve as a mediator of myocardial protective effect by IPC, providing a theoretical basis for further development and utilization of myocardial protective effect of IPC