N-甲基-D-天冬氨酸诱导的正常眼压青光眼小鼠模型的实验研究  

Experimental Study of Normal-Tension Glaucoma Mouse Model Induced by N-Methyl-D-Aspartate

作　　者：刘诗亮[1] 陈媛媛[1] 胡单萍 田凯琳[1] 江梦南 罗雪[1] 沈吟[1] 邢怡桥[1] 

机构地区：[1]武汉大学人民医院眼科中心,湖北武汉430060

出　　处：《武汉大学学报（医学版）》2014年第5期710-715,共6页Medical Journal of Wuhan University

基　　金：国家自然科学基金面上项目(编号:81270998);卫生部公益性行业科研专项(编号:201302015);武汉大学自主科研拔尖创新人才项目(编号:2042014kf0207)

摘　　要：目的:利用N-甲基-D-天冬氨酸(NMDA)诱导的正常眼压青光眼小鼠模型,研究NMDA与视网膜神经节细胞(RGCs)损伤的关系。方法:6周龄C57BL/6J小鼠随机分为低、中、高三个剂量组,玻璃体腔内分别注射NMDA 10,20,30nmol,产生视网膜损伤动物模型。在整体动物水平通过眼底照相、视网膜电图(ERG);在组织学水平通过视网膜HE染色、视神经甲苯胺蓝染色、全视网膜铺片Brn-3a免疫荧光染色及RGCs计数观察术后6h,12h,24h,48h,7dRGCs的损伤情况。结果:NMDA干预后24h,RGCs数量明显减少,内丛状层厚度变薄。眼底视网膜呈苍白色改变,血管迂曲痉挛;ERG显示a波和b波潜伏期的变化不大,b波振幅下降。光镜下可见RGCs密度逐渐降低;视神经轴索呈退行性变,与NMDA的作用时间呈正相关。RGCs计数显示NMDA诱导的RGC减少主要集中于术后1d,24hRGCs数量减少83.97%(P<0.01)。结论:玻璃体腔内注射NMDA可在不影响眼压的情况下诱导RGCs的显著减少和功能损害,与急性青光眼性损伤具有相似性,可为视神经保护研究提供研究条件。Objective：To investigate retinal ganglion cells（RGCs）injury of normal-tension glaucoma mouse model induced by N-methyl-D-aspartate（NMDA）.Methods：Healthy C57BL/6Jmice of 6weeks old were randomly divided into low,medium,and high three groups to receive a single dose of lμl intravitreal injection of three different concentrations of NMDA（respectively 10 nmol,20nmol,and 30 nmol per-injection）.6h,12 h,24h,48 hand 7dafter NMDA injection,mice were killed and the eyes were enucleated.The extent of NMDA-induced neurotoxicity in the retina was quantified by fundus photograph and electroretinogram（ERG）on the whole animal level.The retinas and optic nerves were also processed histologically to determine morphological changes undermicroscope.Results：Cell counting revealed a significant decrease of RGCs after 24 h NMDA treatment in the three dose groups.The thickness of inner plexiformlayer（IPL）was also decreased.30 nmol NMDA treated retina showed a pale color change caused by vasospasm.ERG displayed an obvious decrease of b wave amplitude without obvious delay in a wave and b wave.A progressive degeneration of RGCs and optic nerve axons was seen in NMDA treated eyes related to the time of NMDA administrated.By using antibodies against Brn-3aon retinal whole mounts,a significant loss of RGCs（approximately 83.97%）was shown in 24h（P〈0.01）.Conclusion：Administration of NMDA can result in excitotoxic damage of RGCs without an elevation of intraocular pressure,which is similar to glaucomatous degeneration and of important value in experimental research of glaucoma.

关 键 词：青光眼 动物模型 视网膜神经节细胞 NMDA 兴奋毒性 

分 类 号：R774[医药卫生—眼科]