PHYSICO-CHEMICAL ASPECTS OF RENAL TRANSPORT PROCESSES

肾脏钠和水排泄率的调整构成了 人体细胞外液容量的主要防御系统， 这些物质的摄入量和肾外损失的变化的影响。 同样，调节过滤的碳酸氢盐被重吸收的速率 肾脏的酸碱平衡调节至关重要， 身体 这项研究计划旨在澄清我们对溶质的认识 和水的运输机制，在个人的肾脏水平运作， 小管和毛细血管，这些都是体内平衡调节的基础。 间隙 和微穿刺技术将用于检查实验诱导的 大鼠肾脏中溶质和水转运的变化。 获得的数据 在这些研究中，将在定量模型的框架内进行解释 设计用于提取膜传输参数的值， 清楚地描述正在考虑的过程。 具体来说，这些 研究将（a）评估分子电荷对 与蛋白尿相关的大分子肾小球过滤，（B）发展 并完善尿酸化过程的数学模型， 用于表征碳酸氢盐和碳的跨上皮运动 二氧化碳，并解释高肾内二氧化碳分压， 以及（c）研究溶质和水穿过脉管的运输的动力学 直肠，与尿浓度有关。

Adjustments in the rates of renal sodium and water excretion constitute the major defense of man's extracellular fluid volume against potentially disruptive effects of variations in the intake and extrarenal loss of these substances. Likewise, the modulation of the rate at which filtered bicarbonate is reabsorbed by the kidney is critically important in regulating the acid-base balance of the body. This research program is aimed at clarifying our understanding of solute and water transport mechanisms, operating at the level of individual renal tubules and capillaries, that underly these homeostatic adjustments. Clearance and micropuncture techniques will be used to examine experimentally induced variations in solute and water transport in the rat kidney. The data obtained in these studies will be interpreted within the framework of quantitative models designed to extract values of the membrane transport parameters which most clearly characterize the process under consideration. Specifically, these studies will (a) assess the quantitative effects of molecular charge on the glomerular filtration of macromolecules, in relation to proteinuria, (b) develop and refine mathematical models of the urinary acidification process suitable for use in characterizing the transepithelial movement of bicarbonate and carbon dioxide, and explaining the high intrarenal partial pressure of carbon dioxide, and (c) investigate the dynamics of solute and water transport across the vasa recta, in relation to urinary concentration.