Logo image
Barium inhibition of basolateral membrane potassium conductance in tracheal epithelium
Journal article   Peer reviewed

Barium inhibition of basolateral membrane potassium conductance in tracheal epithelium

Michael J Welsh
The American journal of physiology, Vol.244(6), pp.F639-F645
06/1983
DOI: 10.1152/ajprenal.1983.244.6.F639
PMID: 6859255

View Online

Abstract

Addition of barium ion, Ba2+, to the submucosal bathing solution of canine tracheal epithelium reversibly decreased the short-circuit current and increased transepithelial resistance. The decrease in short-circuit current represented a decrease in the net rate of Cl secretion with no change in the rate of Na absorption. Intracellular microelectrode techniques and an equivalent electrical circuit analysis were used to localize the effect of Ba2+ to an inhibition of the permeability of the basolateral membrane to K. Ba2+ (2 mM) doubled basolateral membrane resistance, decreased the equivalent electromotive force at the basolateral membrane, and decreased the magnitude of the depolarization of basolateral membrane voltage produced by increasing the submucosal K concentration. The inhibition of the basolateral K permeability depolarized the negative intracellular voltage, resulting in both a decrease in the driving force for Cl exit and an estimated increase in intracellular Cl concentration. These studies indicate that there is a Ba2+-inhibitable K conductance at the basolateral membrane of tracheal epithelial cells and that the K permeability plays an important role in the generation of the negative intracellular electrical potential that provides the driving force for Cl exit from the cell.
Membrane Potentials - drug effects Potassium - metabolism Animals Biological Transport, Active - drug effects Dogs Trachea - physiology Mucous Membrane - physiology Electric Conductivity Epithelium - physiology Barium - pharmacology Mucous Membrane - drug effects Cell Membrane - physiology

Details

Metrics

Logo image