BIOLOGY OF HUMAN PIGMENT EPITHELIUM AND BRUCH'S MEMBRANE

与年龄和玻璃疱疹相关的黄斑变性是主要的 美国老年人严重视力丧失的原因 美国和其他国家。其病因和治疗方法尚不清楚。 临床病理研究与Bruch‘s畸形相关 与疾病有关的细胞膜。最近，在一组患者中， 口服元素锌延缓视力丧失 与黄斑变性有关。锌尤其是 在脉络膜视网膜复合体中大量存在。初步研究表明 显示出它是以促进的方式被颜料吸收的 上皮细胞，尽管确切的机制尚不清楚。 人视网膜摄取锌的机制和动力学 使用天然组织和培养细胞的色素上皮 将使用放射性锌作为探针对地层进行调查 实验中使用和不使用阻止、刺激、 减少或竞争吸收。 因为锌是参与合成锌的酶的辅因子 细胞外基质分子，特别是糖结合物 与Bruch膜相关的，我们将研究其影响 不同锌浓度对这些产品生产的影响 分子。一些细胞外基质分子发挥着重要的作用 色素上皮与Bruchs正常黏附的作用 膜，膜被玻璃样变、色素上皮中断 黄斑脱离等黄斑变性改变。vbl.使用 差示萃取和亲和层析程序 计划研究糖共轭化合物的相互作用性质 与布鲁赫膜的其他结构大分子结合。 锌也是参与维持人体健康的酶的辅因子。 细胞完整性，如超氧化物歧化酶。的影响 不同浓度锌对幼虫体内该酶活性的影响 将研究天然和培养的色素上皮。 这些研究应该会提高我们对锌的作用的理解。 在正常视网膜色素上皮的代谢中 特别是细胞外基质的合成 分子和跨皮细胞运输，应该被证明是相关的 黄斑变性等临床重要病症。

Macular degeneration associated with age and drusen is the leading cause of severe visual loss among older individuals in the United States and other countries. Its cause and treatment are unknown. Clinicopathologic studies have associated abnormalities of Bruch's membrane with the disease. Recently, in one group of patients, orally administered elemental zinc retarded the visual loss associated with macular degeneration. Zinc is particularly plentiful in the chorioretinal complex. Preliminary studies have shown it to be taken up in a facilitated fashion by the pigment epithelium, although the exact mechanism is unknown. The mechanism and kinetics of zinc uptake by the human retinal pigment epithelium using both native tissue and cultured cell layers will be investigated using radioactive zinc as a probe in experiments with and without substances that block, stimulate, reduce, or compete for uptake. Because zinc is a cofactor of enzymes involved in the synthesis of extracellular matrix molecules, particularly glycoconjugates associated with Bruch's membrane, we will investigate the effects of different zinc concentrations on the production of these molecules. Some extracellular matrix molecules play important roles in the normal adhesion of the pigment epithelium to Bruch's membrane, which is interrupted by drusen, pigment epithelial detachment, and other changes of macular degeneration. Using differential extraction and affinity chromatographic procedures we plan to investigate the interactive properties of glycoconjugates with other structural macromolecules of Bruch's membrane. Zinc is also a cofactor for enzymes involved in the maintenance of cellular integrity, such as superoxide dismustase. The effects of different concentrations of zinc on the activity of this enzyme in native and cultured pigment epithelium will be studied. These studies should improve our understanding of the role of zinc in the metabolism of the normal retinal pigment epithelium with particular respect to the synthesis of extracellular matrix molecules and transepithelial transport, and should prove relevant to such clinically important conditions as macular degeneration.