摘要
目的研究bcl-2,bax和WTp53蛋白在糖尿病大鼠视网膜组织中的表达及促红细胞生成素(EPO)对其表达的影响。方法48只Wistar大鼠用链脲佐菌素诱导糖尿病(DM),随机分为糖尿病未治疗组和EPO治疗组,分别于1、3、6个月处死大鼠,8只正常Wistar大鼠作为对照组。TUNEL法检测细胞凋亡情况,免疫组织化学法检测大鼠视网膜组织中bcl-2、bax和WTp53蛋白的表达及EPO对其表达的影响。结果DM3和DM6组大鼠视网膜凋亡细胞较正常组和DM1组大鼠增多;与正常组和DM1组大鼠比较,DM3组和DM6组视网膜bcl-2蛋白阳性细胞数减低,bax及WTp53蛋白表达阳性细胞数较多。EPO3、EPO6组与DM3组和DM6组比较,bcl-2阳性细胞数增多,bax和WTp53蛋白表达明显下降(P<0.05)。结论EPO能减少DM大鼠视网膜神经细胞的凋亡,其机制可能与上调bcl-2及下调bax以及WTp53蛋白的表达有关。
Objective Research indicated that the apoptosis exsits not only in vessel endothelial cells and periphery cells but also retinal cells in diabetic retinopathy. This study was to investigate the expression of bcl-2 ,bax and WTp53 in the retina of diabetic rats and the possible pathogenesis of dabetic retinopahty. Methods Diabetes was induced on 48 Wistar rats by intraperitoneal injection of 60 mg/kg streptozotocin（STZ）. Diabetic rats were randomly divided into diabetic mellitus（ DM ）group and erythropoietin（EPO） treating group and all of rats were sacrificed in 1,3 and 6 months （DM 1, D M3, DM6 and EPO1, EPO3, EPO6 groups） and 8 normal Wistar rats were used as controls. Retinal apoptosis was detected by TUNEL technique. The expressions of bcl-2 ,bax and WTp53 were studied by immunohistochemistry. The effects of EPO on the expression of bcl-2, bax and WTp53 were evaluated. Results No TUNEL positive cells were observed in the normal rat retina. In DM3 and DM6 groups,more positive cells were found in comparison with DM1 group. Bcl-2 had a higher expression tensity in normal rat retina and DM1 group which was mainly located in ganglion cell layer（GCL） ,inner nuclear layer（INL） and outer nuclear layer（ONL）. However,less positive cells for bcl-2 were observed in DM3 and DM6 only in GCL and INL. A weaker expression of bax was observed in the normal rat retina and DM1 group mainly in GCL. While in DM3 and DM6 groups, positive expression of bax extended to INL and ONL. WTp53 was weakly expressed in normal group and DM1 group mainly in GCL. The positive expression of bax extended to the whole retina in DM6 group. Compared with the DM group, the experssions of bax and WTp53 were inhibited in EPO group,but the expression of bcl-2 was increased. A statistically significant difference was seen in the expresson of bax, WTp53 and bcl-2 between DM3 and EPO3 or DM6 and EPO6 （P 〈 0.05 ）. Conclusion EPO inhibits retinal apoptosis in diabetic rats probably through downregulating the expression of bax and WTp53 and upregulating the expression of bcl-2.
出处
《眼科研究》
CSCD
北大核心
2008年第9期680-684,共5页
Chinese Ophthalmic Research
