新生鼠脑缺血再灌注后海马CA1区神经胶原纤维酸性蛋白的动态变化及意义

Glial fibrillary acidic protein expression of astrocytes of hippocampal CA1 region after cerebral ischemia- reperfusion in newborn rats

目的 观察新生Wistar鼠脑缺血再灌注后海马CA1区神经胶原纤维酸性蛋白(GFAP)的动态变化,探讨其与缺血性神经元的联系。方法 通过阻断7日龄新生Wistar大鼠右侧颈总动脉45分钟制备脑缺血模型,设置假手术组、缺血再灌注组。通过免疫组化方法和计算机图像分析技术检测二组新生鼠不同时点(灌注后2小时、6小时、12小时、24小时、3天、7天、14天)海马CA1区脑组织GFAP的动态变化。结果 缺血再灌注组海马CA1区GFAP表达在再灌注后24小时开始增高,3天后达高峰,并持续至再灌注后14天,与假手术组比较有显著性差异(P<0.05)。结论 脑缺血再灌注后海马CA1区星形胶质细胞活化及胶原纤维酸性蛋白表达增强在再灌注后14天仍保持在较高水平,星形胶质细胞的活化、增生可能与脑缺血后神经细胞的保护有关。

Objective To observe glial fibrillary acidic protein (GFAP) expression in astrocytes of hippocampal CA1 region after cerebral ischemia-reperfusion. Methods Cerebral ischemia model was made by occluding right carotid artery for 45 minutes in 7-day-old Wistar rats. The rats were randomly divided into ischemia-reperfusion group and sham-operation group. Immunohistochemistry method and computer image analysis technique were used to measure the expression of GFAP in the hippocampal CA1 region at the time of 2h, 6h, 12h, 24, 3d, 7d and 14d after reperfusion. Results The expression of GFAP in cerebral ischemia-reperfusion group increased at 24h after reperfusion and reached the highest level at 3d-4d; the corrected optical density (COD) was significantly higher than that of the sham-operation group. Conclusions The expression of GFAP in hippocampal CA1 region kept at a high-level from 3d to 14d after reperfussion. Activation and proliferation of GFAP-positive astrocytes might play a protective role in the neuron injury due to cerebral ischemia.