Suppression of beat to beat repolarization variability by electrical coupling in guinea pig ventricular myocytes

To examine relationships between intracellular coupling and cardiac repolarization, we electrically connected isolated guinea pig ventricular myocytes to one another with a junctional resistance. Because coupling was achieved by an external circuit that supplied coupling current based solely on transmembrane potential difference, cell-to-cell interactions were considered in their simplest form, independent of ionic diffusion via gap junctions or mechanical interactions between cells.