Activation of PKC affects the ventricular restitution properties and arrhythmogenesis through L‐type Ca+ current

Objective To investigate the role of protein kinase C (PKC) in action potential duration (APD) restitution and ventricular tachyarrhythmias (VAs). Methods and results Rabbits hearts were isolated and prepared for Langendorff perfusion technique. The stimuli–extra‐stimulus (S1–S2) method and dynamic S1 pacing protocol were performed to construct APD restitution and to induce APD alternans or VA, respectively, at 10 sites throughout the ventricular chamber. Administration of phorbol‐12‐myristate‐13‐acetate (PMA) (100 nM) (n = 15) greatly steepened the restitution curves (Smax > 1) (p