Acidosis Impairs the Protective Role of hERG K+ Channels Against Premature Stimulation

Acidosis and the hERG K+ Channel. Introduction: Potassium channels encoded by human ether‐à‐go‐go‐related gene (hERG) underlie the cardiac rapid delayed rectifier K+ channel current (IKr). Acidosis occurs in a number of pathological situations and modulates a range of ionic currents including IKr. The aim of this study was to characterize effects of extracellular acidosis on hERG current (IhERG), with particular reference to quantifying effects on IhERG elicited by physiological waveforms and upon the protective role afforded by hERG against premature depolarizing stimuli.

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