TOXIC METABOLITES OF OXYGEN IN CATARACTOGENESIS.

提出的假设是，O2的活性物质是 氧化应激诱导的晶状体浆损伤的引发剂 膜脂和蛋白质在白内障中的作用。 目的是调查 白内障机制的关键领域涉及氧化 蛋白质和质膜磷脂的过氧化作用。 暴露 透镜质膜在体外受到各种氧化应激， 修饰的内在膜蛋白MP26，将被确定 用SDS聚丙烯酰胺凝胶电泳。 经过同样的治疗， 膜磷脂将通过测量以下物质的形成来评估： 氨基磷脂、丙二醛加合物， 荧光分光光度法 将通过气相色谱法分析脂肪酸， 高效液相色谱法 丙二醛（MDA）和脂质过氧化氢将在 透镜，以观察它们与非饱和损失的可能相关性。 白内障中的脂肪酸 极谱和ESR光谱技术 将被用来探测氧气哦，不含H2 O2和阿霉素半醌 兔眼房水和加小牛透镜的透镜中的自由基 体外微粒体NADPH氧化酶系统。 将试图 鉴定由以下物质聚合形成席夫碱共轭物 氧化应激下透镜和白内障中的氨基磷脂 使用（14 C-）MDA或磷脂酰乙醇胺对人和动物进行了研究。 氧化 体外和前白内障中膜-SH应力诱导交联 半乳糖诱导的兔早期白内障将通过 使用（14 C-）碘乙酰胺。 为了评估酶防御的作用， 白内障，超氧化物的生物活性和非活性形式的分析 歧化酶、过氧化氢酶和GSH过氧化物酶将使用 分光光度法和放射免疫测定法。 抗氧化剂测试 实验性白内障的治疗将继续进行。 逮捕 人类白内障在早期阶段的进展将是巨大的， 帮助病人。 减少污染所带来的经济效益 白内障手术的数量也不容低估。

The hypothesis proposed to test is that reactive species of O2 are the initiators of oxidative stress-induced damage to the lenticular plasma membrane lipids and proteins in cataract. The objective is to investigate the crucial areas of the mechanism of cataract involving oxidation of proteins and peroxidation of phospholipids of plasma membranes. Exposing the lens plasma membranes to various oxidative stresses in vitro, modification of the intrinsic membrane protein MP26, will be determined using SDS polyacrylamide gel electrophoresis. After identical treatment, membrane phospholipids will be assessed by measuring the formation of aminophospholipid.malondialdehyde adduct using TLC, HPLC and spectrofluorometry. Fatty acids will be analysed by gas chromatography and HPLC. Malondialdehyde(MDA) and lipid hydroperoxides will be estimated in lens to observe their possible correlation with the loss of unsaturated fatty acids in cataracts. Polarographic and ESR spectroscopic techniques will be used to detect O2.-, OH., H2O2 and adriamycin semiquinone free radical in aqueous humor, and in lens of rabbit by addition of calf lens microsomal NADPH oxidase system in vitro. Attempts will be made to identify Schiff base conjugate formed by polymerization of aminophospholipids of lens under oxidative stress and in cataracts in the human and animal using (14C-)MDA or phosphatidyl ethanolamine. Oxidative stress-induced cross linking of membrane-SH in vitro, and in precataract and early cataract induced in rabbits by galactose will be determined by using (14C-)iodoacetamide. To assess the role of enzymic defenses in cataracts, analysis of the bioactive and inactive forms of superoxide dismutase, catalase and GSH peroxidase will be done using spectrophotometric technique and radioimmunoassay. Tests of antioxidants in the therapy of experimental cataracts will be continued. Arrest of the progression of cataract in the human at an early stage will be of immense help to the patients. The economic benefit resulting from reduction of the number of surgical procedures for cataracts also must not be underestimated.