大鼠脑缺血后脑组织巢蛋白的表达

Study on the expression of nestin after focal cerebral ischemia in adult rat

目的 探讨脑缺血对巢蛋白表达的影响。方法 按照改良HaruoNagasawa方法建立大鼠大脑中动脉阻塞(CMAO)缺血模型 ,分别在脑动脉栓塞后 12、2 4、4 8、96h、7d及 14d灌注取脑 ,行冷冻切片。以小鼠抗大鼠巢蛋白单克隆抗体为一抗 ,免疫组织化学SABC法染色 ,DAB显色 ,光镜下观察。结果 手术组CMAO后 12h在脑缺血的边缘区开始出现巢蛋白阳性细胞 ,7d后巢蛋白表达达到最高峰 ,14d时在围绕脑梗死边缘的狭窄区域内仍有明显表达 ,但较 7d时有所降低。阳性部位在胞质和细胞突起。假手术组和手术组对侧脑组织未见巢蛋白的明确表达。结论 脑缺血损伤使脑梗死边缘缺血区的反应性星形胶质细胞和新生微血管出现巢蛋白的重新表达 。

Objective To investigate the effect of focal cerebral ischemia on nestin expression in adult rat.Methods Rat cerebral ischemia model was made by modified Haruo Nagasawa method.Brains from rats (n=30) at 12 h,24 h,48 h,96 h,day 7 and day 14 (n=5 per time point) after middle cerebral artery occlusion (MCAO),and control sham operated (n=6) and normal (n=5) rats were processed by single labeled monoclonal antibody and examined by immunohistochemistry for identification of cellular nestin expression.Diaminobenzidine (DAB) was then used as a sensitive chromogen for optical microscopy.Results Nestin positive cells were found in ischemic tissue at the rim of infarction area after 12 hours of MCAO,peaked on day 7,and still distinctly observed on day 14 but less than on day 7.They were not found in control sham operated and normal rats.Conclusions Nestin re expression of reactive astrocyte and microvessels can be induced by CMAO in ischemic tissue.The re expression of nestin,which represents the immature state of cells at embryonic stage,may play a role in tissue repairing process.