Effect of drugs O and C on APD prolongation.

<p><b>A:</b> simulated action potentials of the mouse ventricular model for the epicardial and endocardial cells. Pacing rate was 1 Hz. Relative APD prolongation normalized to the maximum prolongation with I_Ktof completely blocked was determined at various drug concentrations for drug O (○) and drug C (▪) on <b>B:</b> endocardium and <b>C:</b> Epicardium. Pacing rate was 1 Hz.