A Singular Role of I_K1 Promoting the Development of Cardiac Automaticity during Cardiomyocyte Differentiation by I_K1 -Induced Activation of Pacemaker Current.

ABSTRACT: The inward rectifier potassium current (I_K1) is generally thought to suppress cardiac automaticity by hyperpolarizing membrane potential (MP). We recently observed that I_K1 could promote the spontaneously-firing automaticity induced by upregulation of pacemaker funny current (I_f) in adult ventricular cardiomyocytes (CMs). However, the intriguing ability of I_K1 to activate I_f and thereby promote automaticity has not been explored. In this study, we combined mathematical and experimental assays and found that only I_K1 and I_f, at a proper-ratio of densities, were sufficient to generate rhythmic MP-oscillations even in unexcitable cells (i.e. HEK293T cells and undifferentiated mouse embryonic stem cells [ESCs]). We te

SUBMITTER: Sun Y 

PROVIDER: S-EPMC5784831 | biostudies-literature | 2017 Oct

REPOSITORIES: biostudies-literature