Classical Kir channels

Classical Kir channels Classical Kir channels are inwardly rectifying K+ channels with strong inwardly rectifying currents that contribute to highly negative resting membrane potential, prolonged action potential plateau and rapid repolarization in the final stage of action potential. Classical Kir channels are found in various cells such as cardiac myocytes, purkinje fibers, atrial and ventricular tissues. Rectification is caused by intracellular Mg2+ ions and polyamines.