ELECTRON PROBE ANALYSIS OF RENAL CONCENTRATION MECHANISM

本项目的目标是更好地了解肾脏浓缩 机制 冷冻水合散装肾脏的电子探针分析将 使我们能够测量Na、K和Cl的肾脏浓度梯度， 直接沿着纵向皮质-乳头轴。 冷冻分析 含水的大体积肾脏将提供肾小管流体的组成， 肾单位的外髓段和内髓段，无法取样 通过显微穿刺 微量荧光法测定肾组织中尿素 冷冻切片将提供高的皮质-乳头尿素梯度， 分辨率 我们将尝试测量山梨醇的梯度分布 抗利尿剂蓄积。 分析将在三种类型中进行 哺乳动物：大鼠、兔和沙鼠，它们中的每一种可能具有不同的 肾浓缩机制 将在极端利尿剂中进行分析 状态：缺水、渗透性利尿，以及大鼠缺水 通过水负荷利尿。 对肾脏浓缩机制的认识 由于缺乏新数据或依赖旧数据， 没有足够的分辨率。 具有梯度轮廓和成分， 外髓和内髓的小管内液体，我们将能够 评价我们的模型和其他模型的肾内髓质浓度。

The goal of this project is to better understand the renal concentrating mechanism. Electron probe analysis of frozen hydrated bulk kidneys will allow us to measure the renal concentration gradient of Na, K and Cl directly along the longitudinal cortico-papillary axis. Analysis of frozen hydrated bulk kidneys will provide the composition of tubular fluid in outer and inner medullary segments of the nephron, inaccessible to sampling by micropuncture. Microfluorescence urea determination of renal thin frozen slices will provide the cortico-papillary urea gradient at high resolution. We will attempt measuring the gradient profile of sorbitol accumulation in antidiuresis. Analysis will be performed in three types of mammals: rats, rabbits and psammomys, each of which may have a different renal concentrating mechanism. Analysis will performed in extreme diuretic states: Water deprivation, osmotic diuresis, and, in the rat, water diuresis by water load. Understanding of the renal concentrating mechanism is stalled by the lack of new data or by the reliance on old data which do not provide enough resolution. With gradient profile and composition of intratubular fluid in the outer and inner medulla, we will be able to evaluate ours and other models of renal concentration in the inner medulla.