大鼠局灶性脑缺血Activin A及其受体ActRⅡA表达变化及意义

Expression changes of Activin A and ActRⅡA in rats with focal cerebral ischemia

目的探讨大鼠局灶性脑缺血激活素A(ActA)及其受体ⅡA(ActRⅡ)的表达变化规律及意义。方法线栓法制备大鼠大脑中动脉闭塞(MCAO)模型,采用光镜、免疫组化方法检测大鼠局灶性脑缺血后梗死体积、病理变化,免疫组化染色观察ActA、ActRⅡA免疫阳性表达。结果正常组织有极低水平的ActA、ActRⅡA表达,免疫组化显示缺血3h后在周边区ActA、ActRⅡA阳性细胞数量显著高于假手术组(P<0.05),并随缺血时间延长而逐渐增高,于24h达高峰。结论局灶脑缺血损伤可诱导内源性神经元ActA高表达,并可能通过特异性跨膜信号受体ActRⅡA发挥靶源性作用。

Objective To investigate expression of Activin A and ActRⅡA in rat after focal cerebral ischemia.Methods Focal cerebral ischemia was induced by permanent middle cerebral artery occlusion （MCAO） in the rat,injury and infarction volume in brain tissue were observed by HE stain,Activin A and ActRⅡA protein expression was measured by immunohistochemistry.Results Activin A and ActRⅡA protein expressed at a very low level in sham operation group,a strong up-regulation in cortical areas next to the infarct was detected 3 h after MCAO（P0.05）.Expression of Activin A and ActRⅡA increased in response to cerebral ischaemia and reached acme 24 h after MCAO.Conclusions The expression of Activin A and ActRⅡA is gradually increased after focal cerebral ischemia,which has probable protective effects on cerebral injury.