Molecular determinants of cardiac transient outward potassium current (Ito) expression and regulation

Transient outward potassium current in ICC.

Interstitial cells of Cajal (ICC) are the pacemakers of the gut, initiating slow-wave activity. Several ion channels have been identified that contribute to the depolarization phase of the slow wave. Our aim was to contribute to knowledge about the identity and role of ICC potassium channels in pacemaking. Here we describe a transient outward potassium current in cell-attached patches of ICC. T...

Differential responses of rabbit ventricular and atrial transient outward current (Ito) to the Ito modulator NS5806

Transient outward potassium current (Ito) in the heart underlies phase 1 repolarization of cardiac action potentials and thereby affects excitation-contraction coupling. Small molecule activators of Ito may therefore offer novel treatments for cardiac dysfunction, including heart failure and atrial fibrillation. NS5806 has been identified as a prototypic activator of canine Ito This study inves...

Modulation of human cardiac transient outward potassium current by EGFR tyrosine kinase and Src-family kinases.

AIMS The human cardiac transient outward K(+) current I(to) (encoded by Kv4.3 or KCND3) plays an important role in phase 1 rapid repolarization of cardiac action potentials in the heart. However, modulation of I(to) by intracellular signal transduction is not fully understood. The present study was therefore designed to determine whether/how human atrial I(to) and hKv4.3 channels stably express...

Novel mechanism of transient outward potassium channel current regulation in the heart: implications for cardiac electrophysiology in health and disease.

The molecular physiology of the cardiac transient outward potassium current (I(to)) in normal and diseased myocardium.

G. Y. Oudit, Z. Kassiri, R. Sah, R. J. Ramirez, C. Zobel and P. H. Backx. The Molecular Physiology of the Cardiac Transient Outward Potassium Current (I(to)) in Normal and Diseased Myocardium. Journal of Molecular and Cellular Cardiology (2001) 33, 851-872. The Ca(2+)-independent transient outward potassium current (I(to)) plays an important role in early repolarization of the cardiac action po...