Insulin-activated amiloride-blockable nonselective cation and Na+ channels in the fetal distal lung epithelium

Gen Pharmacol. 1995 Jul;26(4):755-63. doi: 10.1016/0306-3623(94)00247-k.

Abstract

1. The apical membrane of fetal distal lung epithelium had two types of amiloride-blockable Na(+)-permeant cation channels; (1) nonselective cation (NSC) channel with a single channel conductance of 27 pS and (2) Na+ channel with a single channel conductance of 12 pS around resting membrane potential. 2. The IC50 of amiloride to the Na+ channel was 1-2 microM, while the IC50 of amiloride to the NSC channel was less 1 microM. The open probability of the Na+ channel was about 10-fold larger than that of the NSC channel. 3. Insulin (100 nM) increased the open probability of both channels.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amiloride / pharmacology*
  • Animals
  • Cells, Cultured
  • Epithelium / drug effects
  • Epithelium / metabolism
  • Insulin / pharmacology*
  • Ion Channels / drug effects
  • Ion Channels / metabolism*
  • Lung / cytology
  • Lung / embryology
  • Lung / metabolism*
  • Membrane Potentials / drug effects
  • Patch-Clamp Techniques
  • Pulmonary Alveoli / cytology
  • Pulmonary Alveoli / drug effects
  • Pulmonary Alveoli / metabolism
  • Rats
  • Sodium Channels / drug effects
  • Sodium Channels / metabolism*

Substances

  • Insulin
  • Ion Channels
  • Sodium Channels
  • Amiloride