成年大鼠液压冲击脑损伤诱导室下区Nestin和GFAP的表达

目的　应用免疫组织化学和免疫荧光双标技术结合激光共聚焦显微镜 ,观察脑损伤后不同时期室下区巢蛋白(Nestin)和胶质酸性纤维蛋白 (GFAP)的表达及其细胞类型。方法　用动液压冲击法建立动物模型 ,用LeicaQ5 0 0IW图像处理系统及免疫组化和免疫荧光双标法分析和显示不同时期 (1、3、5d ,1、2、3、4、6、8周 )Nestin和GFAP的表达变化。结果　损伤 2 4h后 ,室下区有大量Nestin和GFAP的表达 ,且激光共聚焦显微镜观察到有Nestin阳性突起与GFAP共存现象 ,7d左右达到高峰 ,然后随着时间的推移其表达逐渐下降。正常组和假手术组 ,室下区也可见到Nestin和GFAP的表达 ,但与脑损伤组相比较低 (P <0 .0 5 )。结论　脑损伤可诱导室下区Nestin和GFAP的表达 ,Nestin阳性突起与GFAP共存细胞可能具有干细胞特性 ,与神经元的修复有关。

The expression of Nestin and GFAP in adult rat subventricular zone following injury caused by moderate lateral fluid percussion

Objective To investigate the ex pr ession of Nestin and GFAP following injury caused by moderate lateral fluid perc ussion in adult rat subventricular zone, using immunohistochemistry and double i mmunofluorescent labeling techniques combined with confocal laser scanning micro scope analysis. Methods Male Sprague-Dawley rats were divided into 3 group s: normal control, sham operation, and injury groups. The rats of injury group w ere subjected to moderate lateral fluid percussion brain injury (0.2 MPa). The injury group was then subdivided into 1d, 3d, 5d, 1w, 2w, 3w, 4w, 6w and 8w groups (n=6) according to the time elapsed after injury. The express ion and proliferation of Nestin and GFAP at different times were shown with the analytical system of photographs, immunohistochemistry and double immunofluoresc ent labeling. Results In the brain of normal control and sham operation g roups, the expression of Nestin and GFAP, although low, were found. However, the subventricular zone demonstrated a dramatic increase in Nestin and GFAP express ion 24 hours after injury. Double immunofluoscent labeling showed that Nestin po sitive cells were mostly co-stained with GFAP, an astrocyte marker, and signifi cant proliferation was observed after 3 to 7 days. Nestin and GFAP expression wa s down regulated as time went by. Compared with the normal control and sham oper ation groups, the differences were significant (P< 0.05). Conclusion The results suggest that cerebral injury ind uces the expression of Nestin and GFAP, which might favor Nestin and GFAP co-st ained positive cells have the characteristic of embryonic cells, and are related with the neuroprotection against injury caused by moderate lateral fluid percus sion.