Potassium secretion and the regulation of distal nephron K channels.
K-selective channels in the luminal membranes of distal nephron segments form a key pathway for the secretion of K ions into the urine. This process is important to the control of K balance, particularly under conditions of normal or high K intake. This brief review will cover three issues: 1) the identification of apical K channels, 2) the role of these channels in the maintenance of K homeostasis, and 3) the role of aldosterone in this regulatory process. The large amount of literature on renal K transport has been elegantly summarized in a recent review in this journal [G. Giebisch. Am. J. Physiol. 274 (Renal Physiol. 43): F817-F833, 1998]. Here I will focus on a few prominent unsolved problems.
Palmer
L G
LG
Department of Physiology and Biophysics, Weill Medical College of Cornell University, New York, New York 10021, USA. lgpalm@mail.med.cornell.edu
D000450:Aldosterone / Q000502:physiology; D000818:Animals; D006706:Homeostasis; D006801:Humans; D007686:Kidney Tubules, Distal / Q000502:physiology*; D009399:Nephrons / Q000502:physiology*; D011188:Potassium / Q000378:metabolism*; D015221:Potassium Channels / Q000502:physiology*; D024681:Potassium Channels, Calcium-Activated; D024661:Potassium Channels, Inwardly Rectifying; D051640:Small-Conductance Calcium-Activated Potassium Channels
C086989:KCNJ1 protein, human; D015221:Potassium Channels; D024681:Potassium Channels, Calcium-Activated; D024661:Potassium Channels, Inwardly Rectifying; D051640:Small-Conductance Calcium-Activated Potassium Channels; D000450:Aldosterone; D011188:Potassium