The Effects of Beta-Adrenergic Receptor Signalling on Ventricular Conduction System Cell Development

Abstract

Myocardial regenerative treatments with cardiac progenitor cells (CPCs) have been emerging as viable treatment options for myocardial injury. CPCs have the potential to differentiate into working cardiomyocytes and conduction system cardiomyocytes, however mechanisms of differentiation have yet to be studied. In this study the effect of b -adrenergic stimulation, with Isoproterenol (ISO), and inhibition, with metoprolol (METO), were analyzed on ventricular conduction system (VCS) generation from embryonic day 11.5 mice ventricles (containing populations of CPCs). The effects of supplementation of a reducing agent, ascorbic acid (AA), were also studied on enhancement of ISO actions on VCS gene expression. This study showed that both ISO-alone and in combination with AA was able to enhance VCS marker gene expression, through an increase in cAMP. Furthermore, METO was able to negate the ISO-induced increases in VCS gene expression and cAMP levels. This study indicates a role for b-adrenergic receptor signaling in VCS cell development.