视神经挤压伤后星形胶质细胞和轴突反应的免疫组织化学研究(英文)

Immunohistochemical study of the astrocytes and axons responses to crush injury in optic nerve

目的 观察大鼠星形胶质细胞和视网膜节细胞轴突对视神经挤压伤的反应 .方法 用免疫组织化学染色法和计算机辅助免疫组织化学技术研究视神经连续纵向切片 ,定量分析挤压伤后大鼠视神经细胞反应 .结果 挤压伤后 ,视神经轴突标志物 NF- 16 0 ,星形胶质细胞标志物神经胶质纤维酸性蛋白 (GFAP)在直接机械损伤区活力降低并在其后数周内保持低表达 . 3wk时损伤近端神经段 GFAP的光密度为正常的 1.7倍 .在实验观察的 3wk期间挤压伤区近端的 NF-16 0染色明显高于远端 .结论 星形胶质细胞从位于胶质瘢痕和远端之间的损伤区消失可能是视网膜节细胞轴突不能伸长通过损伤区的原因 .

AIM To investigate the response of the astrocytes and retinal ganglion cell (RGC) axons to crush injury in rat optic nerve. METHODS Serial longitudinal optic nerve sections were studied by using immunohistochemical staining and computer enhanced immunohistochemical techniques. Cellular responses of rat optic nerve to crush injury were quantified in different periods. RESULTS Markers, neurofilment 160 (NF 160) for axons and glial fibrillary acidic protein (GFAP) for astrocytes, decreased their activity and remained depressed in the area of direct mechanical injury throughout weeks after crush injury. The optical density of GFAP was 1.7 times above the normal at 3 wk in the nerve segments proximal to the site of injury. Through the 3 week period of study, a significantly higher NF 160 staining is expressed at proximal boundary of the crush injury than that of distal. CONCLUSION Absence of astrocytes from the crush site between the glial scar and the distal stump might explain the failure of axons to elongate across the site of the injury.