糖尿病大鼠早期视网膜功能的损害及其发生机制  

Pathogenesis of retinal damage in diabetic rats at the early stage

作　　者：谢平[1] 刘庆淮[1] 戈应宾[2] 袁孝如[2] 

机构地区：[1]南京医科大学第一附属医院眼科,江苏省南京市210029 [2]南京医科大学生理学系,江苏省南京市210029

出　　处：《中国临床康复》2005年第6期144-146,i006,共4页Chinese Journal of Clinical Rehabilitation

基　　金：南京医科大学科技发展基金资助(NY02025)~~

摘　　要：目的:通过对糖尿病大鼠模型早期视觉功能的变化和糖尿病视网膜的蛋白质氧化损伤进行观察,为研究糖尿病视网膜病变发病机制提供实验依据。方法:实验于2002-10/2004-05在南京医科大学生理学教研室完成。用图形视网膜电图(patternelectroretinogram,PERG)、闪光视网膜电图(flashelectroretinogram,FERG)分别记录正常和链脲菌素(streptozotocin,STZ)诱导的糖尿病大鼠8周以内PERG-q波及FERG-b波潜时,观察糖尿病大鼠早期视网膜功能的改变;以及用免疫组化法和图像处理检测糖尿病大鼠视网膜组织蛋白质损伤产物3-硝基酪氨酸(3-Nitrotyrosine,3-NT)的表达及其改变。结果:糖尿病大鼠从模型建立后第3天开始PERG-q波潜时与正常大鼠相比即有显著延长(P<0.001),而从第1周开始FERG-b波的潜时与正常大鼠相比也显著延长(P<0.001),并且PERG-q波潜时的改变早于FERG-b波潜时的改变;正常大鼠视网膜内无3-NT免疫反应阳性细胞,在糖尿病大鼠视网膜,3-NT阳性反应主要发生在神经节细胞层(ganglioncelllayer,GCL)、并且内核层和外核层均有存在,图像处理显示,糖尿病2,4和8周大鼠视网膜3-NT阳性细胞数差异无显著性意义(P>0.05)。结论:糖尿病大鼠早期在未发现眼底可见的视网膜病变之前就有可用视觉电生理方法检测到的视功能异常,并且糖?AIM:To investigate the pathogenesis of diabetic retinopathy and provide the experimental evidence by observing the changes of visual function and oxidation damage of diabetic retinal matrix protein in the rat model at early stage of diabetes. METHODS:The experiment was completed in the Department of Physiology,Nanjing Medical University from October 2002 to May 2004.Pattern electroretinogram(PERG) and flash electroretinogram(FERG) were used to record normal and streptozotocin induced abnormal PERG q wave latency and FERG b wave latency of diabetic rats within 8 weeks,respectively for an early examination of the change in the retinal function at the early stage of diabetes.Also,immunohistochemistry and image processing were applied to investigate the changes of expression of 3 nitrotyrosine(3 NT),the resulting protein injury product of retinal tissue. RESULTS:In comparison with normal rats,on the 3rd day of the existence of diabetic rat model,the diabetic rats started to have longer(extended) latency of PERG q markedly(P< 0.001),and since the 1st week,it also has longer latency of PERG b(P< 0.001).In addition,the change of wave latency occured earlier in PERG q than in FERG b.In retina of normal rats,no 3 NT was observed;while in retina of diabetic rats,positive reaction of 3 NT was found chiefly in ganglion cell layer(GCL),and some also existed in inner nuclear layer(INL) and outer nuclear layer(ONL).The image processing results showed that there was almost no significant difference in the retina of rats at 2,4 or 8 weeks(P >0.05). CONCLUSION:It is possible to detect the abnormal visual function via electroretinography before the visual identification of retinopathy at the early stage in diabetic rats.The GCL is the first retinal tissue damaged by diabetes,and then the function of the retina prior to GCL is impaired.This indicates that damage of retinal tissue at the early stage of diabetes is primarily targeted at GCL.Oxidative damage might have significant effect on the development of diab

关 键 词：糖尿病视网膜病变 视网膜电描记术 一氧化氮 酪氨酸 链脲菌素 大鼠 

分 类 号：R774.1[医药卫生—眼科]