Hormonal control of renal potassium excretion.
Hormonal control of renal potassium excretion.
复制标题
肾脏钾排泄的激素控制。
DOI：
10.1038/ki.1985.20
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发表时间：
1985
影响因子：
19.6
通讯作者：
Giebisch,GJ
中科院分区：
文献类型：
--
作者：
Field,MJ;Giebisch,GJ
一般认为，肾脏对钾排泄的激素调节主要是醛固酮的功能。然而，最近的研究不仅重新定义了醛固酮在这方面的作用，而且表明其他激素也可能有助于在各种生理条件下通过肾脏维持钾稳态。本次审查将调查什么是已知的这些体液的影响，强调每种药物对肾小管钾转运的具体影响，以及可能的稳态作用，在生理条件下维持钾平衡。本文的局限性在于，仅考虑肾脏的外源性激素，而不考虑肾脏内源性激素的可能影响，关于这一点，具体信息较少。将在我们目前关于肾脏钾处理的概念框架内考虑要讨论的激素作用[1，2]。据认为，钾被自由过滤并经历广泛的近端重吸收，导致向远端小管的最早曲呈现显著恒定的过滤钾负荷分数。大鼠肾单位段的晚期部分在结构和功能上都类似于皮质集合管[3，4]。正是在这些小管中发生钾分泌，并且通过各种管腔和循环因素（包括激素）对该过程进行调节，在很大程度上决定了钾的尿排泄的最终水平[1，2，5]。不同程度的钾重吸收通常发生在沿着髓质集合管的长度;这个过程是不知道直接激素控制。
Hormonal regulation of potassium excretion by the kidney is generally thought of principally as a function of aldosterone. However, recent studies not only redefine the role of aldosterone in this regard but suggest that other hormones may also contribute toward maintenance of potassium homeostasis by the kidney under a variety of physiological conditions. This review will survey what is known of these humoral influences, emphasizing both the specific effect of each agent on renal tubular potassium transport, as well as the possible homeostatic role played by each in maintaining potassium balance under physiological conditions. The limits of the present article are that only hormones extrinsic to the kidney will be considered, leaving aside the possible effects of intrinsic renal hormones, about which less specific information is available.The hormonal actions to be discussed will be considered within the framework of our current conceptions of renal potassium handling [1, 2]. It is thought that potassium is filtered freely and undergoes extensive proximal reabsorption, resulting in the presentation of a remarkably constant fraction of the filtered potassium load to the earliest convolutions of the distal tubule. The late portions of this nephron segment in the rat resemble the cortical collecting tubule, both structurally and functionally [3,4]. It is in these tubular divisions that potassium secretion occurs, and the regulation of this process by a variety of luminal and circulatory factors, including hormones, largely determines the final level of urinary excretion of potassium [1, 2, 5]. A variable degree of potassium reabsorption generally occurs along the length of the medullary collecting ducts; this process is not known to be under direct hormonal control.