Chronic atrial ionic remodeling by aldosterone: potentiation of L-type Ca2+ channels and its arrhythmogenic significance

It is widely accepted that aldosterone induces atrial fibrillation (AF) by promoting structural changes, but its effects on the function of primary atrial myocytes remain unknown. We have investigated this point in adult rat atrial myocytes, chronically exposed to the hormone. This treatment produced larger amplitude of Ca2+ transients, longer action potential (AP) duration, and higher incidence of unsynchronized Ca2+ oscillations. Moreover, it...