Relation between BK-α/β4-mediated potassium secretion and ENaC-mediated sodium reabsorption.

ABSTRACT: The large-conductance, calcium-activated BK-α/β4 potassium channel, localized to the intercalated cells of the distal nephron, mediates potassium secretion during high-potassium, alkaline diets. Here we determine whether BK-α/β4-mediated potassium transport is dependent on epithelial sodium channel (ENaC)-mediated sodium reabsorption. We maximized sodium-potassium exchange in the distal nephron by feeding mice a low-sodium, high-potassium diet. Wild-type and BK-β4 knockout mice were maintained on a low-sodium, high-potassium, alkaline diet or a low-sodium, high-potassium, acidic diet for 7-10 days. Wild-type mice maintained potassium homeostasis on the alkaline, but not acid, diet. BK-β4 knockout mice could not maintain potassium homeostasis on either diet. During the last 12 h of diet, wi

SUBMITTER: Wen D 

PROVIDER: S-EPMC4077913 | biostudies-literature | 2014 Jul

REPOSITORIES: biostudies-literature