血管紧张素Ⅱ介导大鼠心肌缺血预处理的初步探讨

PRELIMINARY STUDY OF ISCHEMIC PRECONDITIONING MEDIATED BY ANGIOTENSION Ⅱ ON THE RAT HEART

在Langendorff灌注大鼠心脏模型上，观察了血管紧张素任预处理对心肌缺血再灌注损伤的作用，及其受体阻断剂Losartan对心肌缺血预处理的影响。结果：10－7mol／L血管紧张素Ⅱ预处理心脏，明显改善了随后缺血再灌注所造成的心肌损伤；在预处理前及预处理过程中，用10-6mol／LLosartan灌流心脏，可消除预处理的保护作用。提示外源性血管紧张素Ⅱ能够模拟缺血预处理的心肌保护作用，而心肌组织源性血管紧张素Ⅱ可能是参与大鼠心肌缺血预处理的重要介质。

For the study of the effect of An-giotension Ⅱ on the myocardial ischemia precondi-tioning, we observed the influence of Angiotension Ⅱ and Losartan, the Angiotension Ⅱ receptor an-tagonist, on the ischemia reperfusion injury and is-chemic preconditioning by using Langendorff model.The results showed that myocardial injury caused by ischemia reperfusion could be significantly reduced if pretreated with 10-7 Angiotension Ⅱ. The effect of the Angiotension Ⅱ on the myocardia pretection could be abolished by using 10-6mol/L Losartan be-fore and during the preconditioning procedure. The results indicate that exogenous Angiotension Ⅱ can mimic the myocardial protective effect of the is-chemia preconditioning. So we deduce that endoge-neous tissue Angiotension Ⅱ might be an important mediator involving in the myocardial precondition-ing.