Rapid and slow components of delayed rectifier current in human atrial myocytes

Abstract

(1) IK in human atrium shows kinetically distinguishable rapid and slow components. (2) These components correspond to E-4031 sensitive and resistant currents. (3) The kinetics and voltage dependence of the rapid (E-4031 sensitive) and slow (E-4031 resistant) components correspond to properties previously described in guinea pig myocytes. These findings have important potential implications for understanding the mechanisms of human atrial repolarisation and its regulation by the autonomic nervous system and antiarrhythmic drugs.