牛磺酸对急性低氧大鼠视网膜内网状层损伤的防护效应  

Protective effects of taurine on inner plexiform layer of retina in rats exposed to hypobaric hypoxia

作　　者：陈卡[1] 糜漫天[1] 陈芳[1] 许红霞[1] 曾凯宏[1] 张亚洁[1] 

机构地区：[1]第三军医大学军事预防医学院营养与食品卫生学教研室,重庆市营养与食品安全重点实验室,重庆400038

出　　处：《第三军医大学学报》2008年第23期2176-2179,共4页Journal of Third Military Medical University

基　　金：全军医学科研"十一五"计划专项课题(06Z028);重庆市营养与食品安全重点实验室开放课题(2007);第三军医大学科研创新基金(2007XG19)~~

摘　　要：目的观察牛磺酸(Taurine,Tau)对模拟急性低氧(hypobaric hypoxia,H)条件下大鼠视网膜内网状层(inner plexiform layer,IPL)形态结构及功能的影响。方法64只SD大鼠随机分为标准饲料组和牛磺酸干预组(2.4g/100g)。营养干预14d后进行连续1、3d或7d模拟5000m低氧处理,同时分别设立常氧对照即标准饲料正常对照组和牛磺酸干预正常对照组。低氧处理后立即测定视网膜振荡电位(oscillatory potentials,OPs),观察内网状层超微结构,并结合免疫荧光染色法测定突触蛋白(synapsin,SYS)平均光密度。结果低氧1、3d两组大鼠OPs波较正常对照潜伏时间长、幅值低,低氧7d接近正常,其中牛磺酸干预组低氧处理后其OS2幅值均高于标准饲料组(P<0.05),OS2潜伏时间在低氧3d时较标准饲料组低氧3d时短(P<0.05)。超微结构显示急性低氧后标准饲料组IPL轴突内线粒体肿胀、空化,树突终末微管溶解,突触稀少,突触带弯曲、短小,突触囊泡缺失;牛硫酸干预组突触结构清晰,突触囊泡较多。免疫组织荧光化学染色显示各组大鼠IPL内均见SYS阳性表达,急性低氧1、3d视网膜SYS平均光密度值低于对照(P<0.05),其中牛磺酸低氧1d组SYS表达较低氧1d组强(P<0.05)。结论牛磺酸对急性低氧大鼠视网膜内网状层结构和功能具有一定的保护效应。Objective To investigate the effects of taurine on the structure and function of retinal inner plexiform layer （IPL） of rats exposed to hypobaric hypoxia. Methods Sixty-four rats were randomly divided into 2 groups： normal diet group （N）, taurine supplemented group （T）. Rats from normal diet group were fed with normal chew for 14 d, and then further divided into 4 subgroups, normoxia control （NC）, and the groups （NH） who were placed into low pressure chamber to imitating 5 000 m high altitude for 1, 3 or 7 d respective- ly. Rats fed with 2.4% taurine supplemented chew for 14 d were divided into 4 subgroups, that is, TC groups, and those in hypobaric hypoxia for 1, 3 or 7 d respectively （ TH groups）. After the hypoxia treatment, IPL function was evaluated by testing oscillatory potentials （OPs） with RETI port system, by observing uhrastrac- ture of IPL with transmission electron microscope, and by determining the average density of synapsin with immunohistofluorescence method. Results Prolonged latency and lower amplitude in OPs were found in rats exposed to 1 or 3 days＇ hypobaric hypoxia of both NH and TH groups, but for those rats having 7 days＇ exposure, the latency of their OPs reduced to relative normal value, but the amplitude was significantly lower in eompari- son to NC and TC groups （ P 〈 0.05 ）. There were significant difference in the latency of OS2 wave between the NH rats and TH rats after 3 days＇ exposure （P 〈 0.05 ） , and the OS2 amplitude in TH groups were significantly higher than those in NH groups （P 〈 0.05）. IPL of rats in NH groups showed swelling and swollen mitochondria in axon, disintegrated dendritic microtube, scarce synapses with depleted vesicle, while TH group displayed distinct synapses with abundant vesicles. Synapsin was mainly distributed in IPL of every group. Compared with NC group, the density of synapsin decreased in rats exposed to hypoxia for 1 or 3 d in both groups （ P 〈 0.05 ）. But in TH 1 d group, the synapsin

关 键 词：牛磺酸 急性低氧 视网膜 内网状层 

分 类 号：R151.41[医药卫生—营养与食品卫生学] R364.4[医药卫生—公共卫生与预防医学]