WATER AND ELECTROLYTE MOVEMENT IN RENAL TUBULES

本提案的总体目标是建立有意义的 哺乳动物肾单位的结构-功能关系。 将进行三项主要调查，其中两项 代表了正在进行的研究的自然进展， 通过发展新的 方法和新的合作关系。 三 研究领域包括异噬和自噬 在肾小管，描绘的网站和机制， 集合管中的质子和碳酸氢盐运输，以及 继续对肾脏进行形态学检查。 更 具体地说： 1. 自噬和异噬的过程将是 在哺乳动物近端小管中进行评价，以更好地表征 亚细胞器、蛋白质和相关的 分子物质经历降解。 将特别强调 将组织蛋白酶B mRNA表达的测量作为一种 更好地理解这一机制的手段， 控制自噬泡-溶酶体中的组织蛋白酶B水平 车厢 2. 研究了质子和质子转移的位点和亚细胞事件， 将评价碳酸氢盐转运沿着哺乳动物 收集管的结构和功能， 主细胞和闰细胞。 严重依赖将 用于转运蛋白和离子的鉴定 通过使用高度特异性的抗体探针， 免疫细胞化学和光亲和标记技术。 3. 交感神经纤维的分布 哺乳动物肾脏与神经效应器之间的关系 连接和肾小管上的α-和β-肾上腺素受体， 将检查血管。 将特别强调 α-和β-肾上腺素受体的鉴定 肾实质在超微结构水平与使用 针对受体的特异性抗体， 放射性标记肾上腺素能受体的放射自显影定位 使用光亲和标记的拮抗剂。 这些调查将需要应用各种 生理、生化和形态学技术，包括 光学显微镜，透射和扫描电子显微镜， 体外光镜和电镜放射自显影 离体肾小管微灌注，超微酶 分析和免疫细胞化学。

The overall objective of this proposal is to establish meaningful structural-functional relationships in the mammalian nephron. Three major lines of inquiry will be pursued, two of which represent natural progressions of ongoing research that will be expanded and intensified through the development of new methodologies and new collaborative relationships. The three areas of inquiry include examination of heterophagy and autophagy in the renal tubule, delineation of the sites and mechanisms of proton and bicarbonate transport in the collecting duct, and continued morphological exploration of the kidney. More specifically: 1. The processes of autophagy and heterophagy will be evaluated in the mammalian proximal tubule to better characterize the manner in which subcellular organelles, proteins and related molecular substances undergo degradation. Special emphasis will be placed on the measurement of cathepsin B mRNA expression as a means of obtaining a better understanding of the mechanism that controls cathepsin B levels in the autophagic vacuole-lysosomal compartment. 2. The sites and subcellular events involved in proton and bicarbonate transport will be evaluated along the mammalian collecting duct by examining the structure and function of the principal cells and the intercalated cells. Heavy reliance will be placed on identification of transport proteins and ion channels through the use of highly specific antibody probes and immunocytochemical and photoaffinity labelling techniques. 3. The distribution of the sympathetic nerve fibers in the mammalian kidney and the relationship between neuroeffector junctions and alpha- and beta-adrenoceptors on tubules and vasculature will be examined. Special emphasis will be placed on the identification of alpha- and beta-adrenoceptors throughout the renal parenchyma at the ultrastructural level with the use of specific antibodies directed against the receptors and by autoradiographic localization of radiolabelled adrenergic antagonists using photoaffinity labelling. These investigations will require the application of a variety of physiologic, biochemical and morphologic techniques including light microscopy, transmission and scanning electron microscopy, light and electron microscopic autoradiography, in vitro microperfusion of isolated kidney tubules, ultramicroenzyme analysis and immunocytochemistry.