Expanding role of SK channels in cardiac electrophysiology

Heart Rhythm. 2014 Jul;11(7):1233-8. doi: 10.1016/j.hrthm.2014.03.045. Epub 2014 Mar 25.

Abstract

The small conductance calcium-activated potassium (SK) channels are an important group of potassium-selective ion channels. SK channels display more pronounced expression in the atrium relative to the ventricle. Current evidence relating to the functional role of SK channels in the atria is conflicting and whether these channels contribute to atrial repolarization under physiological circumstances is a matter of debate. Multiple studies have, however, reported that SK channels are important mediators of proarrhythmogenic electrical remodeling in the atria. In keeping with their expression profile, SK channels do not appear to play a prominent role in ventricular repolarization. SK channels represent potentially attractive therapeutic targets for atrial fibrillation. A number of pharmacological modulators of SK channels have been tested in animal models of atrial fibrillation. However, these studies have also demonstrated inconsistent results and have raised important questions regarding the proarrhythmogenic potential of SK channel modulation. These findings have important implications for drug development. This review summarizes the role of SK channels in cardiac electrophysiology and discusses the potential role of these channels as therapeutic targets.

Keywords: Arrhythmia; Atrial fibrillation; Cardiac conduction; SK channels; Ventricular fibrillation.

Publication types

  • Review

MeSH terms

  • Animals
  • Anti-Arrhythmia Agents / pharmacology*
  • Arrhythmias, Cardiac / drug therapy
  • Arrhythmias, Cardiac / physiopathology*
  • Electrophysiologic Techniques, Cardiac
  • Heart / physiopathology*
  • Heart Conduction System / physiopathology*
  • Humans
  • Small-Conductance Calcium-Activated Potassium Channels / drug effects
  • Small-Conductance Calcium-Activated Potassium Channels / physiology*

Substances

  • Anti-Arrhythmia Agents
  • Small-Conductance Calcium-Activated Potassium Channels