胰岛素对缺血-再灌注心脏的保护作用

Cardioprotection of insulin during ischemia-reperfusion

目的:论证胰岛素和热休克蛋白(HSP)在心肌缺血-再灌注损伤中的保护作用,探讨胰岛素和热休克蛋白之间的联系。方法:成年雄性Sprague-Dewleyr大鼠被分为五组:①对照组、②胰岛素处理组、③缺血-再灌注组、④缺血、胰岛素和再灌注处理组、⑤缺血、再灌注和胰岛素处理组。用电子显微镜行超微结构观测。左心室心肌的 HSP70以酶联免疫吸附法测定。用化学比色法测定SOD活力及MDA含量。结果:HSP70含量在胰岛素处理组、缺血-再灌注组和缺血、胰岛素和再灌注处理组均较对照组高(P<0．01);在缺血、再灌注和胰岛素处理组较其他四组明显升高(P<0．01)。结论:胰岛素导致心肌HSP70的表达,且加强对缺血-再灌注反应的HSP70合成。

Objective ： To study the cardioprotective effect of insulin and heat shock protein during ischemia-reperfusion and to discuss the relationship between insulin and heat shock proteins. Methods： Adult male Sprague-Dawley rats were assigned to 5 groups：①control group. ②insulin treatment group. ③ischemia and reperfusion group. ④ischemia, insulin and reperfusion group. ⑤ischemia, reperfusion and insulin treatment group. Ultrastructural changes were studied by electron microscopy. HSP70 of left ventricle myocardium was analyzed by enzyme-linked immunosorbent assay （ELISA）. Vagor of SOD and content of MDA was determined by chemical colorimetry. Results ： HSP70 was increased in insulin treated hearts, ischemia-reperfusion treated hearts, or ischemia, insulin and reperfusion treated hearts [ （47.02±3.63） ng/mg protein, （50.71 ±3.07） ng/mg protein, （51.38±2.76） ng/mg protein,P 〈 0.01 ] vs control [ （30.07 ± 5.83 ） ng/mg protein ]. HSP70 was increased in ischemia,reperfusion and insulin treated hearts [ （ 75.82± 13.24 ） ng/mg protein ] compared to control, insulin only, ischemia and reperfusion only ,or ischemia ,insulin and reperfusion treated hearts （P 〈 0.001 ）. Conclusion：Insulin caused expression of myocardial HSP70 and potentiated HSP70 synthesis in response to ischemia and reperfusion.