【作者】 刘志敏；

【导师】 应大君；

【作者基本信息】 第三军医大学 ， 解剖学， 2006， 硕士

【摘要】 目的大鼠活体内研究视神经损伤后晶状体蛋白对视网膜神经节细胞（retinal ganglioncells RGCS）保护作用和轴突再生作用。方法1、在正常Long-evens大鼠玻璃体腔注射不同浓度(1×10^-3g/L,1×10^-4g/L,1×10^-5g/L)晶状体蛋白5μl,5天后分别用光镜和电镜观察视网膜及神经节细胞。2、在大鼠视神经切断伤模型中用荧光金逆行示踪技术观察损伤后1周、2周、3周节细胞存活率及小胶质细胞活化的情况。3、损伤后1周、2周、4周、8周,在大鼠视神经钳夹伤模型中使用麦芽凝集素（WGA）顺行示踪技术及损伤后4周、8周、12周电镜观察轴突再生的情况。4、伤后1周、2周、4周、8周行F-VEP检查,观察大鼠视功能恢复情况。结果1、大鼠玻璃体腔注射1×10^-3g/L、1×10^-4g/L、1×10^-5g/L晶状体蛋白,光镜观察各组视网膜各层结构正常,注射1×10^-3g/L组电镜观察RGCs线粒体稍肿胀,线粒体嵴轻微损伤,注射其余两浓度组RGCs无异常。2、玻璃体腔注射生理盐水在视神经切断伤后1周、2周、3周RGCs数分别下降为正常组的51.5%、17.9%、12.2%,而混合晶状体蛋白组为70.6%、32.2%和15.2%,均显著高于生理盐水对照组（P＜0.01）,两周时高于牛血清白蛋白对照组（P＜0.01）。3、玻璃体腔注射晶状体蛋白眼较生理盐水对照眼晚出现胶质反应,伤后1周、2周、3周小胶质细胞计数均少于对照眼。4、视神经损伤后玻璃体腔注射晶状体蛋白组有更多轴突纤维尽快通过损伤区,通过损伤区的再生轴突的数目增多,促进F-VEP振幅恢复。结论1、玻璃体腔注射1×10^-4g/L、1×10^-5g/L晶状体蛋白5μl对视网膜及RGCs无毒副作用。2、玻璃体腔注射晶状体蛋白在视神经损伤后1-3周可提高RGCs存活率,减轻伤后视网膜中胶质反应,使活化的小胶质细胞数目减少,并延迟活化过程。3、视神经损伤后,玻璃体腔注射晶状体蛋白不但能够保存相对多的轴突纤维和促进轴突再生,而且能够部分的改善视功能。更多还原

【Abstract】 To investigate the survival of retinal ganglion cells（RGCS） after optic nerve cut and the regeneration of axons after the incomplete optic nerve injury in vivo treated by intravitreous injection of mixed crystallines.Methods1.Adult male Long-evans rats were divided into 3 experimental groups and a normal control group.5μcrystallines of different concentration(1×10^-3g/L、1×10^-4g/L、1×10^-5g/L) were injected into vitreous cavity and the changes of the retina and RGCs were observed by light and electron microscope after 5 days.2.To evaluate the effect of survival of RGC in vivo by means of intravitreous injection of the mixed crystallines.Flurogold retrograde tracing was used to stain RGCs and actived microglia.3.WGA anterograde tracing and electron microscopy were also applied to evaluate axonal regeneration of RGCs.4.F-VEP was performed before the injury and every time point after injury.Results1、The retinal changes of light microscope were within normal limit.Mild damage in some mitochondrial crista of RGCs was observed only in the group with crystallines 1×10^-3g/L intravitreous injection.2、Intravitreous injection of mixed crystallines can rescue some RGCs,and the survival rate of RGCs significantly increased from 51.5%,17.9%and 12.2%at 1w,2w and 3w post-injury to 70.6%,32.2%and 15.2%respectively,compared to the control eyes（p＜0.01）.3、Treatment of intravitreous injection of mixed crystallines can reduce the glial response to injury,decrease and retard activation of microglia,with the consequence of lowering non-selective phagocytosis of degenerating but still surviving RGCs.4、Treatment of intravitreous injection of mixed crystallines can sprout and improve more axons to regenerate unhindered,and the amplitude of F-VEP showed obvious recovering on 4-8weeks after the injury.Conclusions1.There is no toxicity of crystallines(1×10^-4g/L and 1×10^-4g/L) by intravitreous injection).2.Intravitreous injection of mixed crystalline can rescue some RGCs and reduce activation of microglia.3.Intravitreous injection of mixed crystalline can clear the path for axons to sprout and improve the regeneration of the axons as well as partly restore the visual function.更多还原