Intracellular calcium ions as regulators of renal tubular sodium transport. Academic Article uri icon

Overview

abstract

  • This review addresses the putative role of intracellular calcium ions in the regulation of sodium transport by renal tubules. Cytoplasmic calcium-ion activities in proximal tubules of Necturus are less than 10(-7) M and can be increased by lowering the electrochemical potential gradient for sodium ions across the peritubular cell membrane, or by addition of quinidine or ionomycin to peritubular fluid. Whereas lowering of the peritubular Na concentration increases cytosolic [Ca++] and [H+], ionomycin, a calcium ionophore, raises intracellular [Ca++] without decreasing pHi. The intracellular calcium-ion level is maintained by transport processes in the plasma membrane and membranes of intracellular organelles, as well as by calcium-binding proteins. Calcium ions inhibit net transport of sodium by reducing the rate of sodium entry across the luminal cell membrane. In the collecting tubule this inhibition is caused, at least in part, by an indirect reduction in the activity of the amiloride-sensitive sodium channel.

publication date

  • September 15, 1986

Research

keywords

  • Body Fluids
  • Calcium
  • Intracellular Fluid
  • Ion Channels
  • Kidney Tubules, Proximal
  • Sodium

Identity

Scopus Document Identifier

  • 0022497313

Digital Object Identifier (DOI)

  • 10.1007/BF01725557

PubMed ID

  • 2430134

Additional Document Info

volume

  • 64

issue

  • 18