关键词： 二硫化碳/毒性；视网膜疾病；山楂/治疗应用；大枣/治疗应用；枸杞/治疗应用

【摘要】目的探讨复方山楂饮对二硫化碳(carbon disulfide CS₂)毒性视网膜损害的防护作用。方法30只健康新西兰白兔随机分为正常对照组、染毒对照组及治疗组3组。染毒及治疗组用CS₂吸入式染毒，每日连续3小时，每周连续6天，共3周。治疗组在染毒前口服复方山楂饮8．3ml/kg。实验3周后取兔眼视网膜组织作光镜及透射电镜检查。结果光镜及电镜均显示染毒对照组视网膜各层细胞均呈明显变性改变。光镜显示染毒对照组视细胞内外段结构破坏，神经纤维层疏松，神经节细胞空泡变性。电镜显示染毒对照组视细胞突触空泡化改变，突触后间隙加大，突触小棒消失。治疗组视网膜各层细胞结构大致正常。结论复方山楂饮可提高CS₂染毒兔对CS₂的耐受能力，对视网膜具有一定程度的保护作用。

中国图书资料分类法分类号R774．1R932．5

Histological study of haw drink compound in protecting against experimental carbon disulfide toxic damage of relina

TIAN Qingfen,GUO Xirang,YIN Weijing,et al．

Henan Institute of Ophthalmology,Zhengzhou 450003,China

【Abstract】PurposeTo investigate the protective effect of“haw drink compound”against carbon disulfide (CS₂)toxic retinal damage．MethodsThirty healthy white adult New Zealand rabbits were divided at random into 3 groups:the normal control group,the exposure control group and the treatment group．The experimental rabbits were contaminated by inhaling CS₂ for3 continuoues hours in 6 consecutive days in a week for totaly 3 weeks．The rabbits in the treatment group were given haw drink compound before containation．After 3 weeks of the experiment,the retinal tissues of the rabbits were examined with light microscope and transmissing electronmicroscope（TEM）．ResultsThe ultrastructures of the retinal tissues of the exposure control group were more abnormal than those of the treatment group and the normal control group．TEM showed that every layer cell of the retinal in the exposure control group showed apparent degenerative changes ,but that in the treatment group showed apparent degenerative changes,but that in the treatment group was nomal．The light microscpic picture showed that the inner segments and the outer segments of photoreceptors construction were destroyed,the nerve fiber layer was loose and ganglion celles vacuolated in the retinat of the exposure control group．TEM showed that The photorecepter synapses were vacuolated,the postsynaptic space became wider and the synaptic sticks disappered．ConclusionHow drink compound can improve the tolerance to CS₂ toxicity in inducing the retinal damage ofrabbits．

【Key words】Carbon dioxide/toxicityRetinal diseasesCRATAEGUS PINNATIFIDA/therapeutic useZIZIPHUS JUJUBA/therapeutic useLYCUMBARBARUM/therapeutic use

二硫化碳(CS₂)为亲神经血管性的致脂质过氧化毒物^［1］，CS₂中毒与自由基反应密切相关^［2］。CS₂对视网膜视神经的毒性损害已有报道^［3］，但其机制尚无定论。我们曾通过动物试验证明其与脂质过氧化反应有关^［4］，但防治尚无有效的疗法。我们选用具有抗氧化功能的复方山楂饮作为治疗药物，对CS₂毒性视网膜损害进行了实验病理研究，进一步探讨CS₂毒性视网膜损害与脂质过氧化的关系以及复方山楂饮对其的防护作用。

1材料与方法

1．1材料毒剂为CS₂，分析纯，上海试剂四厂产品。染毒柜为有机玻璃静式染毒实验柜，体积为：55cm×44cm×60cm。复方山楂饮为山楂、枸杞、大枣等抗氧化中药组成。山楂产地河南辉县(北山楂)，枸杞产地宁夏，大枣产地河南内黄县。制剂在河南省人民医院制剂室制备，工艺过程为：取山楂、枸杞、大枣加水煎熬、滤过、防腐、消毒及无菌包装，按每瓶500 ml装瓶备用。实验动物新西兰白兔由河南医科大学动物中心提供，共30只，雌雄各15只，体重2．2～3．0 kg，笼养，眼科研究所动物房提供标准饲料。眼前节及眼底检查均正常。随机分为3组，每组10只，雌雄各半，1组为正常对照组，2组为染毒对照组，3组为治疗组。

1．2试验方法①染毒方法：吸入式中毒，柜内CS₂质量浓度为1000 mg/m^3［5］。实验兔吸入CS₂，每日连续3小时，每周连续6天，周末休息1日，共3周。②治疗组：在染毒前1小时口服复方山楂饮8．3 ml/kg;③染毒对照组：染毒前1小时口服生理盐水20 ml;④正常对照组：既不染毒，亦不服药。

所有兔在染毒前及染毒后1，2，3周时均双眼分别检测视网膜电图，共4次。实验3周结束时，均于兔心脏内注射空气处死后摘除眼球，每只眼一半视网膜作生化检测，一半作病理检查。

1．3视网膜组织病理检查方法①光镜检查：福尔马林固定，常规脱水，石蜡包埋，HE染色。②透射电镜检查：将分离的视网膜组织用2．5％戊二醛固定后，切成1 mm×4 mm的组织块，丙酮逐级脱水，1%四氧化锇后固定，常规方法制备，苏木精、淀粉蓝混合染色，半薄切片定位，LDK型切片机作超薄切片，枸椽酸铅、醋酸铀双重染色，透射电镜作超微结构观察。

2结果

2．1电生理及生化检测3周后染毒兔视网膜电图b波幅明显降低^［6］。生化检测染毒兔视网膜脂质过氧化反应明显增强，超氧化物歧化酶(superoxide dismutase，SOD)活性明显降低^［4］，而治疗组则无此种明显改变^［6］。

2．2组织病理学观察①正常对照组兔眼光、电镜检查均正常；(图1，2)。②染毒对照组兔眼光、电镜检查均异常。光镜主要表现为视网膜变性性改变。光感受器外段囊样膨胀及破裂，排列紊乱呈深伊红染色，部分内、外核层变薄，核淡染，细胞疏松，细胞核极性消失，内界膜、神经纤维层疏松，淡染，神经节细胞空泡变性，核染色质固缩(图3)。透射电镜显示视细胞突触空泡化改变，突触后间隙加大，突触小棒消失(图4，5)，视细胞外节松散、紊乱。神经节细胞线粒体变性，水肿，嵴模糊，树突粗面内质网溶解，溶酶体增多。RPE微绒毛变短、粗大，排列紊乱。毛细血管内皮细胞肿胀，扭曲，囊样改变，管腔内红细胞肿胀呈短棒状。③治疗组：7只兔眼光、电镜显示正常，3只兔眼有轻度异常。光镜下表现为神经纤维层疏松，节细胞染色淡(图6)。电镜仅见毛细血管内皮细胞基底膜有断续现象(图7)，但色素上皮细胞基底膜平滑完整。色素上皮细胞部分微绒毛排列紊乱变短，部分微绒毛排列整齐。但是视细胞突触正常(图8，9)，神经节细胞大致正常，视细胞及外节正常。

图1正常对照组兔眼视网膜光镜像。视网膜组织各层细胞均正常HE×400图2正常对照组兔眼视网膜电镜像。视细胞突起和突触小带正常HE×28000图3染毒对照组兔眼视网膜光镜像。视细胞内外段结构破坏，外界膜模糊，神经纤维层疏松，核淡染，核染色质固缩（箭），神经节细胞空泡变性HE×400

Fig．1The light microscopic picture of normal rabbit retinaHE×400Fig．2The transmissing electronmicroscopic picture of the rabbit retina of the normal control group．The photoreceptor synaptic sticks are normalHE×28000Fig．3The light microscopic picture of the rabbit retina of the exposure control group．The inner segments and the outer segments of photoreceptors construction are destroyed,the outer limiting membrane is indistinct,the nerve fiber layer is loose,the nuclear stain is light, the chromatin of nucleus shrinks（arrow），andganglion celles are vacuolatedHE×400