TNF-α诱导大鼠视网膜神经节细胞凋亡的研究  

Study on TNF-α-mediated apoptosis of retina ganglion cell

作　　者：崔新华[1] 王竫华[1] 王大博[1] 

机构地区：[1]青岛大学医学院附属医院眼科,266003

出　　处：《眼科研究》2008年第2期108-112,共5页Chinese Ophthalmic Research

摘　　要：目的研究肿瘤坏死因子α(TNF-α)对视网膜神经节细胞(RGCs)凋亡的诱导作用以及凋亡相关基因bcl-2和bax在该过程中的表达。方法健康成年Wistar大鼠30只,随机分成5个实验组和1个对照组,分别玻璃体腔注射不同质量浓度的TNF-α和生理盐水。2周后处死动物,制备光镜和电镜标本,并行免疫组织化学染色,进行计算机图像分析。结果当TNF-α质量浓度≥10μg/mL时,光镜下可见神经节细胞层细胞的排列开始变得紊乱无序,细胞间距加大,且随着TNF-α质量浓度的增加而显著;电镜下可见到细胞凋亡征象,各组均未见典型的坏死神经节细胞及炎性细胞浸润;bcl-2和bax在神经节细胞层的表达强度均随着TNF-α质量浓度的增加而增强。结论一定质量浓度(≥10μg/mL)的TNF-α可引起RGCs的凋亡;在一定时间(2周)内,RGCs的凋亡随TNF-α质量浓度的增加而增加;bcl-2和bax参与了TNF-α所引起的RGCs的凋亡的调节。Objective Apoptosis is the main way in the gradually losing of retina ganglion cells （RGCs） in glaucoma. Recently researches proved that TNF-α was key factor in RGCs apoptosis. The aim of this study was to investigate TNF-α-induced apoptosis of RGCs and detect the expression of apoptosis-related genes, bcl-2 and bax. Methods Thirty Wistar rats were randomly divided into five experimental groups and one control group. 2 μL TNF-α at 2.5,5,10,20,40μg/mL concentration was injected into vitreous cavity of rats in experimental groups respectively,and normal saline was used to the control group. After 2 weeks of vitreous injection, experimental rats were sacrificed and the retinal tissues were prepared for the examination of light and electronic microscopy. Results No obvious histological alteration was seen, and the almost normal cellular organs were also found in 2.5 and 5 μg/mL of TNF-α groups. The alignment of RGCs became disordered and the distance among the cells was widened,and the abnormalities of chromatin, nuclear membrane and mitochondrion were also found in 10,20 and 40μg/mL of TNF-α groups,however,no necrosis and inflammatory cell infiltration were observed in every group. The brown-yellow staining of bcl-2 and bax in cytoplasm of RGCs were identified in over 5 μg/mL of TNF-α groups, and the mean optical density value of bcl-2 and bax in RGCs layer was gradually enhanced with the increase of TNF-α concentration over 5 μg/mL of TNF-α groups compared with control group（P 〈 0.05 - 0. 01 ）. Conclusion Over 101xg/mL of TNF-α mediates RGCs apoptosis within 2 weeks in a concentration-dependent manner. Bcl-2 and bax participate in the apoptosis mechanism of RGCs induced by TNF-α.

关 键 词：肿瘤坏死因子Α 视网膜神经节细胞 细胞凋亡 BCL-2 BAX 

分 类 号：R775[医药卫生—眼科]