Figure 1.
Ranolazine (RAN) reversibly shortens action potential (AP) duration (APD) of ventricular myocytes isolated from canine failing hearts (HF).
Panel A: Representative APs of single left ventricular cardiomyocytes. Superimposed APs were recorded at a pacing rate of 0.5 Hz in the absence of drug (control), in the presence of ranolazine (10 μM) and after drug washout.
Panel B: Effect of ranolazine on APD at 90% repolarization (APD90) of ventricular myocytes stimulated at a rate of 0.5 Hz. Ranolazine at concentrations of 5, 10 and 20 μM significantly and reversibly shortened APD90. Data were pooled from 3 non-failing and 6 failing hearts. All APs longer than 2 s were excluded.
n= number of myocytes; * p < 0.05 vs. HF (ANOVA followed by Bonferroni’s post-hoc test against HF).