大鼠视神经吸断伤后相关分子表达的变化

目的：研究视神经损伤后神经胶质细胞去分化的程度及相关分子的表达。方法：成年雄性大鼠视神经吸断伤后,采用免疫组织化学、原位杂交组织化学结合计算机图像分析,检测视神经巢蛋白、胶质纤维酸性蛋白 (GFAP)、髓鞘碱性蛋白(MBP)、神经纤维丝(NF)以及 Nogo-A mRNA 在伤后3、7、14和28 d 4个不同时相点的表达。结果：视神经伤后,巢蛋白表达上调,在28 d 时表达最高；GFAP 表达先下调,7 d 时最低,随后逐渐上调； MBP 表达上调,呈先上升后降低的趋势；NF 表达呈明显下降趋势；Nogo-A mRNA 表达呈上升趋势,3 d 到7 d 的变化最显著。结论：视神经损伤后相关分子表达提示其神经胶质细胞可去分化为神经前体细胞或神经干细胞,但这些前体细胞或干细胞呈不利于神经再生的状态。

Expression of related molecules after optic nerve transection in rats

Objective:To investigate the dedifferentiation of glia cells and the expression of related molecules after optic nerve(ON)injury.Methods:The expressions of Nestin,glia fibrillary acidic protein(GFAP),myelin bas- ic protein(MBP),neurofilament protein(NF)and Nogo-A mRNA were observed by immunohistochemistry and in situ hybridization bistochemistry with Biosens Digital Imaging System at 3,7,14 and 28 days after ON tran- section in adult male rats.Result:The expression of nestin was up-regulated and the peak expression appeared at 28th day post-operation.The expression of GFAP was down-regulated initially with the lowest level appearing at the 7tb day after ON injury and then up-regulated gradually.MBP level increased firstly and then decreased.The expression of NF was down-regulated remarkably.Levcl of Nogo-A mRNA presented an ascending trend,espe- cially from the 3rd day to the 7th day.Conclusion:These changes of related molecules expression suggest that the glia cells might be induced to dedifferate into neural progenitor cells or neural stem cells,but these cells are not benefitial for ON regeneration.