Mitochondria-dependent regulation of Kv currents in rat pulmonary artery smooth muscle cells

A L Firth, K H Yuill, Sergey V Smirnov

Research output: Contribution to journalArticlepeer-review

20 Citations (Scopus)

Abstract

Voltagegated K+ (Kv) channels are important in the regulation of pulmonary vascular function having both physiological and pathophysiological implications. The pulmonary vasculature is essential for reoxygenation of the blood, supplying oxygen for cellular respiration. Mitochondria have been proposed as the major oxygen-sensing organelles in the pulmonary vasculature. Using electrophysiological techniques and immunofluorescence, an interaction of the mitochondria with Kv channels was investigated. Inhibitors, blocking the mitochondrial electron transport chain at different complexes, were shown to have a dual effect on Kv currents in freshly isolated rat pulmonary arterial smooth muscle cells (PASMCs). These dual effects comprised an enhancement of Kv current in a negative potential range (manifested as a 5- to 14-mV shift in the Kv activation to more negative membrane voltages) with a decrease in current amplitude at positive potentials. Such effects were most prominent as a result of inhibition of Complex III by antimycin A. Investigation of the mechanism of antimycin A-mediated effects on Kv channel currents (I-Kv) revealed the presence of a mitochondria- mediated Mg2+ and ATP-dependent regulation of Kv channels in PASMCs, which exists in addition to that currently proposed to be caused by changes in intracellular reactive oxygen species.
Original languageEnglish
Pages (from-to)L61-L70
Number of pages10
JournalAmerican Journal of Physiology-Lung Cellular and Molecular Physiology
Volume295
Issue number1
Early online date8 May 2008
DOIs
Publication statusPublished - Jul 2008

Fingerprint Dive into the research topics of 'Mitochondria-dependent regulation of Kv currents in rat pulmonary artery smooth muscle cells'. Together they form a unique fingerprint.

Cite this