胶质纤维酸性蛋白在视神经横断后大鼠视网膜神经胶质细胞中的表达

The expression of glial fibrillary acidic protein in rat retina glial cells following optic nerve transection

目的探讨胶质纤维酸性蛋白(GFAP)在视神经横断后大鼠视网膜神经胶质细胞中的表达情况及可能的意义。方法制作大鼠视神经横断模型,分别于术后1、3、7d取材,制作视网膜矢状位冰冻切片,用谷氨酰胺合成酶(GS)标记视网膜Mller细胞,行GS/GFAP免疫荧光双标。提取视网膜总RNA行GFAP Real-Time PCR半定量分析。结果正常大鼠视网膜中GFAP阳性染色仅位于视网膜内层的星形胶质细胞上。术后1d,在Mller细胞上出现GFAP的诱导表达,术后3d,GFAP在Mller细胞上的表达进一步增强,术后1周,GFAP在Mller细胞上的表达保持在较高水平,Real-Time PCR半定量分析与以上结果吻合。结论视神经横断后GFAP在Mller细胞上的诱导表达是Mller细胞对视网膜损伤产生的—种胶质化反应,GFAP的表达量与病程进展相一致。GFAP在Mller细胞上的诱导表达尤其在足板处的强烈表达可能对视网膜神经节细胞具有保护作用。

Objective To investigate the expression of GFAP in rat retina following optic nerve transection and its significance. Methods Optic nerve transection mode was made to examined the reactive changes of miiller glial cells. Three rats were killed at each of the points at 1,3,7 days post-operation for sagital sections, Double labeled immunofluorescence was used to ascertain the cellular localization and the change of GFAP in retina. Total RNA was extracted from the retina from the experimental and control rats for Real-time PCR analysis. Results GFAP expression was observed only in astrocytes in the normal adult rat retina. GFAP expression was induced and upregulated in mature Muller glial cells following optic nerve transection. Real-time PCR analysis confirmed the marked change in expression of GFAP with course of disease. Conclusion Present results suggest that the induced expression of GFAP in Muller glial cells is a reactivechange in retina subjected to optic nerve transection. The induced expression of GFAP in Muller glial cellsespecially at their end-feet suggests a potential neuro protective mechanism in neuronal degeneration.