摘要
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 。
Objective:To study the effects of Ischemia Preconditioning (IPC) on the expression of HSP70 mRNA during ischemia reperfusion injury.Methods:Eight dogs were evenly divided into IPC group and control group.Dogs in IPC group were subjected to 5min left anterior descending coronary artery occlusions and 10min reperfusions for 4 times before 1h ischemia,and myocardial tissues from left ventricular free walls were excised after IPC,and at 1,2,4h of reperfusion as well as control group.Total RNA was extracted and subjected to Dot blotting.The myocardial ultrastructure of 1h reperfusion in two groups was observed under transmission electron microscope (TEM).Results:The levels of HSP70 mRNA in IPC and control groups before 1h ischemia were 2.65±0.21 and 2.36±0.19(P<0.05),and at 1h,2h reperfusions were 2.98±0.12 and 2.75±0.16(P<0.05),3.26±0.18 and 3.19±0.14(P<0.05).But no difference between the two groups at 4h reperfusion(2.52±0.24 and 2.47±0.20,(P>0.05).IPC can induce early expression of HSP70 mRNA in dog myocardium,and the expression levels increase in the following reperfusion process.Conclusion:It is suggested that HSP70 may act as a mediator for the protection of myocardium during ischemia reperfusion injury.
出处
《山东医科大学学报》
2000年第2期163-165,共3页
Acta Academiae Medicinae Shandong
关键词
缺血预处理
心肌缺血
再灌注损伤
热休克蛋白
Preconditioning
Myocardial ischemia
Myocardial reperfusion injury
Heat-shock proteins
