新肾素血管紧张素系统通路与脑心综合征关系的实验研究

Objecitve: To invesgate the role of the new RAS in the development of Cerebro-cardial syndrome. To invesgate the pathogenesis of the Cerebro-cardial syndrome.Methods: The healthy Wistar rats (250±30g) were devided into four groups randomly: the blank control group, the model group, the losartan group, the losartan＋A779 group.Each group was devided into two subgroup: 4 hour and 24 hour(n=8). The rats were intraperitoneally injected with hydral 0.3g/kg, The cerebral ischemia model was induced by processed thread inside the right middle cerebral artery，the ECG was moniterd simutaniously. The model group was intragastrically given distilled water with equal volume 30 minutes before the experiments. The losartan group was intragastrically given losartan (10mg/kg) 30 minutes before the experiments, as well as the losartan+A779 group. A779 was intraperitoneally given (120ng/kg)as soon as the processed thread inside the middle cerebral artery in The losartan＋A779 group. Acquire the blood from carotid artery, then centrifugate the blood to get the plasma which was stored at --80℃.Anterior left ventricular wall myocardial tissue was divided into two slips, one was fixed with paraform, the other was stored at -80℃. The cerebral slices were stained with TTC to clarify the success of model creation, and the infarct rate was inspected in each model group. The content of AngⅡin the myocardial tissue and the plasma was detected by chemical luminescence.The content of Ang-(1-7) in the myocardial tissue and the plasma was detected by ELISA. The extent of myocardial damage was detected by HE. The expression of Ang-(1-7) and AngⅡof myocardial tissue was detected by immunohistochemistry.Result: The model group showed severe myocardial injury. In losartan group, myocardial injury is reduced. Myocardial jury in losartan + A779 group was heavier than that of the losartan group. HE results of each 24 hour group of myocardial was heavier than that of each 4 hour group. Compared with the blank control group, the content of Ang II in plasma of the model group was rised(P <0.01). Compared with the model group, Ang II of the lostarn group was rised(P <0.01). Ang II of lostarn+A779 group was lower than that of lostarn group(P <0.01). Compared with the blank control group, the content of Ang-(1-7) in plasma of the model group was decreased(P <0.01); Ang-(1-7) of lostarn group was higher than that of the model control group (P <0.01); Ang-(1-7) of lostarn+A779 group was lower than that of the model group and the lostarn group(P <0.01).The content of Ang II and Ang-(1-7) of each 24 hour group in plasma was respectively rised accordingly with the extension of time(P <0.01). The changes of Ang II and Ang-(1-7) of each group in myocardial tissue were consistent with that of plasma.Conclusion: Ang-(1-7) gets involved in the development of cerebro-cardial syndrome by mas receptor, and plays a role in protection of the myocardial injury induced by cerebral infraction.