Pacemaker current exists in ventricular myocytes.
I(f), the "cardiac pacemaker current," is a nonselective cation channel activated on hyperpolarization in primary and secondary pacemaker regions of the mammalian heart. The cardiac pacing rate can be modulated by shifting the activation of I(f) to more positive (faster pacing) or more negative (slower pacing) voltages. We report for the first time the presence of this pacemaker current in ventricular myocytes. The potential importance of this observation to the mechanism of differentiation of nonpacing regions in the heart is discussed.
Yu
H
H
Department of Physiology and Biophysics, SUNY Stony Brook 11794-8661.
Chang
F
F
Cohen
I S
IS
D000818:Animals; D002412:Cations / Q000378:metabolism; D004285:Dogs; D004594:Electrophysiology; D006168:Guinea Pigs; D006329:Heart Conduction System / Q000502:physiology*; D007473:Ion Channels / Q000502:physiology*; D009206:Myocardium / Q000166:cytology; D011690:Purkinje Fibers / Q000502:physiology; D016276:Ventricular Function
D002412:Cations; D007473:Ion Channels