目的:观察结膜下注射庆大霉素对家兔视网膜的影响。方法:选择健康家兔10只,体质量2.0～2.5kg,双眼无病变。分为4组,实验组3组每组3只6眼,对照组1只2眼,对照组每天双眼结膜下注射生理盐水,实验组3组分别每天双眼结膜下注射庆大霉素5000U,10000U和20000U,实验组和对照组每天穿刺抽取房水及玻璃体,用全自动血药浓度监测分析仪测量其浓度;第3d取视网膜制作光镜标本,观察视网膜细胞组织形态改变;使用TUNEL组织凋亡检测试剂盒进行凋亡检测。结果:结膜下注射庆大霉素的3组家兔中,前房及玻璃体内庆大霉素药物浓度随注射天数增加;前房及玻璃体腔内药物浓度与结膜下注射之庆大霉素剂量正相关,玻璃体内药物浓度远低于前房内药物浓度(P<0.05);在光学显微镜下对比对照组,实验组家兔视网膜出现视锥、视杆细胞层变薄,溶解,节细胞层空泡形成甚至溶解,内外颗粒层细胞数变少等现象,且随着给药剂量增加,病理改变越明显;免疫组织化学显示:实验组内颗粒层凋亡细胞计数较对照组明显增加,且给药浓度越高,凋亡细胞计数越多。结论:研究显示,结膜下注射氨基糖甙类抗生素可引起视网膜病理改变及细胞凋亡增加,且其视网膜毒性与给药剂量正相关。

AIM:To investigate the effects of subconjunctival gentamicin injection on rabbit retina.METHODS:Ten healthy rabbits weighted 2.0-2.5kg without binocular disorders were selected,and divided into 4 groups,3 experimental group(3 rabbits 6 eyes of each group),1 control group(1 rabbit 2 eyes).3 experimental groups received binocular subconjunctival gentamicin injection 5000μ,10000μ,20000μrespectively.Control group received binocular normal saline injection.Aqueous and vitreous fluid were extracted from these ten rabbits every day and measured the concentration with TDX/FLX.At the third day,retinas were taken to make light microscope samples in order to observe cytohistomorphology of retina,and using TUNEL to detect the apoptosis.RESULTS:The gentamicin concentration of rabbit aqueous and vitreous fluid increased as the subconjuctival injection dosage increased.Obvious pathological changes were observed in retina of experimental group.The number of apoptotic retina cells of the experimental group evidently increased than which in the control team.CONCLUSION:Subconjunctival injection of gentamicin should be prohibited in clinic for its obvious retinal toxicity.

R774.1

中国深圳市科技计划资助项目(No.200902037)~~