ION TRANSPORT IN COLLECTING CELL CULTURES

我们的目标是了解离子输运性质及其机制， 皮质集合管不同类型细胞的调节 （CCD）。 具体目标是：1。继续表征离子传输 在培养的CCD细胞中表达的机制。 将混合CCD培养物 用于确定离子转运的机制，以及ADH的作用， 醛固酮和异丙肾上腺素在不同的转运蛋白上。 2.研究 细胞内和细胞外pH对细胞生物学和转运的影响 CCD单分子膜的功能。 2.1.为了评估 不同细胞类型的比例和形态学变化， 对培养物酸碱状态改变的反应。 2.2.到 建立位于顶端的转运蛋白的pH依赖性， 不同细胞的基底外侧膜。 我们会研究 三种细胞类型的传导和非传导离子转运途径 在基础条件下，以及它们对急性和慢性变化的反应， 基底侧和/或顶侧溶液的pH值。 3.为了描述， 结构和功能上均质的单层主细胞 和闰细胞。 3.1.主动脉的超微结构和功能 将研究细胞单层：我们将在细胞膜上表征 水平基线离子传输机制及其调节， 激素（ADH、醛固酮、异丙肾上腺素）。 3.2.的同质培养物 插入细胞，最初被鉴定为α或β细胞， 将在有和没有激素刺激的情况下进行研究。 特别 将考虑细胞转化的可能性 类型到另一个。 CCD细胞的单层将使我们能够收集基本的 关于细胞和单膜离子转运机制的信息 程度. 它们也应该是生物化学和分子生物学的有用工具。 问题研究 均质培养将允许定量研究， 不同类型的相邻细胞的混杂影响。 这些 研究有助于我们了解肾小管的发病机制， 离子转运缺陷，如肾小管酸中毒、浓缩 缺陷和K+分泌异常。

We aim to understand the ion transport properties and the mechanisms of its regulation in the different cell types of the cortical collecting duct (CCD). Specific aims are: 1. Continue characterizing the ion-transport mechanisms expressed in CCD cells in culture. Mixed CCD cultures will be used to identify mechanisms of ion transport, and the effects of ADH, aldosterone, and isoproterenol on the different transporters. 2. To study the effects of intra and extracellular pH on the cell biology and transport functions of CCD monolayers. 2.1. To assess the modifications in the proportion of the different cell types and the morphological changes in response to alterations in acid-base status of the cultures. 2.2. To establish the pH dependence of the transporters located in the apical and basolateral membranes of the different cells. We will examine the conductive and nonconductive ion-transport pathways of the three cell types under basal conditions and their responses to acute and chronic changes in pH of basolateral and/or apical solutions. 3. To characterize, structurally and functionally, homogeneous monolayers of principal cells and intercalated cells. 3.1. The ultrastructure and function of principal- cell monolayers will be studied: We will characterize at the cell-membrane level the baseline ion transport mechanisms and their regulation by hormones (ADH, aldosterone, isoproterenol). 3.2. Homogeneous cultures of intercalated cells, initially identified as either alpha or beta cells, will be studied with and without hormonal stimulation. Special consideration will be given to the possibility of transformation of a cell type to another. Monolayers of CCD cells will allow us to gather basic information on ion transport mechanisms at the cellular and single-membrane levels. They should also be useful tools for biochemical and molecular studies. Homogenous cultures will permit quantitative studies without the confounding influences of neighboring cells of different type. These studies could help our understanding of the pathogenesis of renal tubule ion-transport defects, such as renal tubular acidosis, concentration defects and K+ secretion abnormalities.