CELLULAR PD AND ION ACTIVITIES IN RENAL PROXIMAL TUBULES

该项目的主要目的是更详细地审查 这些因素之间高度相互依赖的关系， 细胞内钠离子活性和净钠转运 氢和钾离子的系统。 离体灌注近端 曲小管和近端直小管段 皮质将比较关于运输和细胞调节 功能协调发展的 拟议实验的具体目标是：1） 检查细胞外和细胞内pH对阴离子的影响， 腔膜和基底外侧膜的阳离子选择性渗透2） 研究导致差异的潜在机制， 基底外侧膜的表观碳酸氢盐电导， 近曲小管和近直小管3）检查现象 在曲小管中的电势振荡 运输和细胞调节pH值之间的相互作用和4） 研究细胞钾的调节， 在腔膜上。 测量将采用常规的 微电极和双管离子选择性电极， 钠钾氯和氢 长期目标是 阐明细胞离子交换和肾 运输过程维持电解质和水的稳态控制 体液的平衡。

The principal aims of this project are to examine in greater detail the highly interdependent relationships between those factors which regulate intracellular sodium activity and net sodium transport and the transport systems for hydrogen and potassium ions. Isolated perfused proximal convoluted and proximal straight tubule segments from the superficial cortex will be compared with regard to transport and cell regulatory functions. The specific aims of the proposed experiments are to: 1) examine the effect of extracellular and intracellular pH on anion and cation perm-selectivity of the luminal and basolateral membranes 2) investigate the underlying mechanisms which result in the difference in apparent bicarbonate conductance of the basolateral membrane between the proximal convoluted and proximal straight tubule 3) examine the phenomenon of electrical potential oscillations in convoluted tubules with respect to the interaction between transport and cellular regulation of pH and 4) investigate the regulation of cellular potassium with particular emphasis on the luminal membrane. Measurements will be made with conventional microelectrodes and with double barreled ion selective electrodes for sodium, potassium, chloride, and hydrogen. The long term goals are to elucidate the basic mechanisms by which cellular ion exchanges and renal transport processes maintain homeostatic control of electrolyte and water balance of the body fluids.