中等剂量（20Gy）电离辐照后早期大鼠脑内S—100免疫反应胶质细胞的动态变化

应用大鼠半脑 2 0Gy照射模型和免疫组织化学方法 ,研究电离辐射对脑内S 10 0蛋白表达和变化的影响。于照射后不同时间点 (2 4h ,1,2 ,3,4周 ) ,观察S 10 0蛋白免疫反应胶质细胞在大鼠脑内的分布和数量变化。结果发现 :在上述时间点 ,脑内各部位S 10 0蛋白免疫反应细胞数量进行性增加 ,伴有S 10 0免疫反应胶质细胞的胞体逐渐增大和突起增多 ,与正常对照组具有明显的差异。S 10 0蛋白作为脑内星形胶质细胞功能活化状态的重要指标 ,其表达的显著增加 ,提示脑内星形胶质细胞可能参与了大鼠脑辐射后的早期病理过程。

Early dynamic distribution of S-100-immunopositove glial cells in the rat brain after medium dose (20 Gy) ionizing irradiation

The influence of medium dose ionizing irradiation on S 100 protein expression level was studied in the rat brain by immunohistochemistry.The S 100 protein immunoreactive cells in rat brain were observed at different time points ranging from 24 h,1 week,2 weeks,3 weeks and 4 weeks after irradiation (single fraction maximal dose of 20 Gy).Compared with that of control animals, the number of S 100 immunoreactive glial cells in the irradiated rat brains increased gradually.Furthermore, more S 100 immunoreactive glial cells with multiple long processes and hypertrophic cell bodies were also observed in these areas.Since S 100 protein is regarded as a sensitive marker for astroglial activation, the increased expression of S 100 protein in the brains has suggested that astroglial cells may be involved in the early pathological processes of the ionizing irradiation injury of rat brain.