FACTORS AFFECTING RETINAL SUSCEPTIBILITY OF DEGENERATION

这项拟议的研究试图找出哪些因素是 光感受器细胞对 退化。感光细胞的敏感度随时间变化。 年龄和视网膜(地形图)位置的作用。实验 旨在检验结构和化学成分的变化 光感受器细胞的特性是它们的变化的基础 易退化的。光感受器特异性变性将 通过将大鼠的视网膜暴露在恒定的光线下而产生。vbl.使用 形态测量和视网膜电描记术，严重程度 光诱导的退化将被确定为年龄和 视网膜区域。其他几个参数，如棒材外段 长度、磁盘堆积密度、更新率、脂视蛋白比和 视紫红质浓度将在非暴露动物中进行检测，也作为一种 年龄和视网膜区域的功能，以评估它们在影响 光感受器对退化的敏感性。 一种检验感兴趣的假设的新方法将利用孤立的 体外保存大鼠和青蛙视网膜的延长视网膜电流图 正在录音。视网膜将在含有以下物质的补充培养液中孵化 不同水平的营养物质被认为是对感光细胞的保护 退化。黄曲霉毒素引起的视网膜电信号恶化 将监测亚铁离子，随后将对视网膜进行检查 显微镜。通过这种方式，补充营养物质的能力在 改变感光细胞对退化的敏感性将是 评估过了。 拟议的实验应有助于阐明 光感受器细胞对退化的敏感性和它们的 保护能力。这些信息可能有助于努力 制定预防类似视网膜退行性变的措施 在人类中的机制。

The proposed research seeks to identify those factors which are responsible for increases in the susceptibility of photoreceptor cells to degeneration. The susceptibility of photoreceptor cells varies as a function of age and (topographical) location in the retina. Experiments are designed to test the hypothesis that changes in structural and chemical properties of the photoreceptor cells underlie the variation in their susceptibility to degeneration. Photoreceptor-specific degeneration will be produced by exposing the retina of rats to constant light. Using morphometric and electroretinographic techniques, the severity of light-induced degeneration will be determined as a function of age and retinal region. Several other parameters, such as rod outer segment length, disk packing density, renewal rate, lipid to opsin ratio and rhodopsin concentration will be examined in non-exposed animals, also as a function of age and retinal region, to evaluate their role in influencing photoreceptor susceptibility to degeneration. A new approach to testing the hypothesis of interest will utilize isolated rat and frog retinas maintained in vitro for extended electroretinogram recording. Retinas will be incubated in supplemented media containing various levels of nutrients thought to protect against photoreceptor cell degeneration. Electroretinogram deterioration caused by incubation with ferrous ion will be monitored and retinas subsequently will be examined by microscopy. In this manner, the capability of supplemented nutrients in altering the susceptibility of photoreceptor cells to degeneration will be assessed. The proposed experiments should help to elucidate the basis for changes in both the susceptibility of photoreceptor cells to degeneration and their protective capability. This information could be helpful in efforts to devise preventative measures against retinal degenerations of similar mechanism in humans.