氯沙坦对大鼠脑缺血再灌注后血管紧张素Ⅱ和加压素的影响及脑保护作用

The effects of Losartan on angiotensin Ⅱ.vasoperssin concentration of plasma and brain,and its protective effect on brain in the cerebral ischemia reperfusion rat

目的探讨氯沙坦对大鼠脑缺血再灌注后血浆、脑组织中血管紧张素Ⅱ(angiotensinⅡ,ANGⅡ)、脑组织中血管加压素(vasopressin,AVP)的影响和脑保护作用及两者的相互关系。方法制作大鼠大脑中动脉栓塞模型(middlecerebralarteryocclusion,MCAO),用Longa法评分,测定神经功能;干湿法测定脑水肿;TUNEL法凋亡染色。观察脑梗死灶半暗带区凋亡细胞的变化;用放免法测定血浆、脑匀浆ANGⅡ及脑匀浆AVP,并作统计分析。结果结果显示实验组的神经功能缺损、脑水肿、半暗带区细胞凋亡程度均明显轻于缺血未治疗组(P<0.05,P<0.01,P<0.01),血浆中的ANGⅡ水平则显著高于缺血未治疗组(P<0.01),但脑局部ANGⅡ实验组与缺血未治疗组间无显著差异(P>0.05),实验组脑组织中的AVP明显低于缺血未治疗组(P<0.01)。结论氯沙坦可通过影响大鼠缺血再灌注脑局部ANGⅡ和AVP发挥一定的脑保护作用。

Objective To sduty the effects of Losartan on angiotensin Ⅱ （ANG Ⅱ ）,vasopressin（AVP） concentration of plasma and brain and its protective effect on brain in the cerebral ischemia reperfusion rats. Methods Longa score was used to appraise the degree of neurological deficit,dry-wet method to value cerebral edema, TUNEL apoptotic staining to observe changes of apoptotic cells of the penumbra respectively, radioimmunoassay to detect ANG Ⅱ and AVP concentration of plasm and cerebral after middle cerebral artery occulusion（MCAO） model was made. Results The degree of the neurological deficit,cerebral edema,and the count of apoptotic cells in the penumbra were significantly approved in Losartan group than that in the ischemia,control group （P〈 0, 05,P〈 0. 01 ,P〈0.01 ）,respectively. ANG Ⅱ concentration of plasm was significant higher,cerebral AVP lower in Losartan group than in the ischemia control group （P〈0.01）,respectively. But cerebral ANG Ⅱ concentration had no significant difference between the two groups （P〉 0. 05）. Conclusion Losartan may have some prophylactic and therapeutic effects on ischemia reperfusion brain impairment.