Regulation of cation-selective channels in liver cells

S. D. Lidofsky, A. Sostman, J. G. Fitz

Research output: Contribution to journalArticle

20 Scopus citations

Abstract

In liver cells, cation-selective channels are permeable to Ca2+ and have been postulated to represent a pathway for receptor-mediated Ca2+ influx. This study examines the mechanisms involved in the regulation of these channels in a model liver cell line. Using patch-clamp recording techniques, it is shown that channel open probability is a saturable function of cytosolic [Ca2+], with half-maximal opening at 660 nM. By contrast, channel opening is not affected by membrane voltage or cytosolic pH. In intact cells, reduction of cytosolic [Cl-], a physiological response to Ca2+-mobilizing hormones and cell swelling, is also associated with an increase in channel opening. Finally, channel opening is inhibited by intracellular ATP through a mechanism that does not involve ATP hydrolysis. These findings suggest that opening of cation-selective channels is coupled to the metabolic state of the cell and provides a positive feedback mechanism for regulation of receptor-mediated Na+ and Ca2+ influx.

Original languageEnglish (US)
Pages (from-to)231-236
Number of pages6
JournalJournal of Membrane Biology
Volume157
Issue number3
DOIs
StatePublished - Jul 14 1997

Keywords

  • Calcium
  • Hepatocytes
  • Nonselective cation channels
  • Patch clamp
  • Signaling

ASJC Scopus subject areas

  • Biophysics
  • Physiology
  • Cell Biology

Fingerprint Dive into the research topics of 'Regulation of cation-selective channels in liver cells'. Together they form a unique fingerprint.

  • Cite this