Potassium modulates electrolyte balance and blood pressure through effects on distal cell voltage and chloride. Academic Article uri icon

Overview

abstract

  • Dietary potassium deficiency, common in modern diets, raises blood pressure and enhances salt sensitivity. Potassium homeostasis requires a molecular switch in the distal convoluted tubule (DCT), which fails in familial hyperkalemic hypertension (pseudohypoaldosteronism type 2), activating the thiazide-sensitive NaCl cotransporter, NCC. Here, we show that dietary potassium deficiency activates NCC, even in the setting of high salt intake, thereby causing sodium retention and a rise in blood pressure. The effect is dependent on plasma potassium, which modulates DCT cell membrane voltage and, in turn, intracellular chloride. Low intracellular chloride stimulates WNK kinases to activate NCC, limiting potassium losses, even at the expense of increased blood pressure. These data show that DCT cells, like adrenal cells, sense potassium via membrane voltage. In the DCT, hyperpolarization activates NCC via WNK kinases, whereas in the adrenal gland, it inhibits aldosterone secretion. These effects work in concert to maintain potassium homeostasis.

publication date

  • January 6, 2015

Research

keywords

  • Blood Pressure
  • Electrolytes
  • Potassium, Dietary

Identity

PubMed Central ID

  • PMC4332769

Scopus Document Identifier

  • 84920607517

Digital Object Identifier (DOI)

  • 10.1016/j.cmet.2014.12.006

PubMed ID

  • 25565204

Additional Document Info

volume

  • 21

issue

  • 1