Electrophysiological effect of resveratrol on pacemaker cells in sinoatrial node of rabbits / 中国药理学与毒理学杂志

ABSTRACT

AIM In order to investigate whether resveratrol can be used as a kind of antiarrhythmic drug, the electrophysiological effect of resveratrol on pacemaker cells in sinoatrial node was studied. METHODS Using intracellular microelectrode technique to record the action potential of pacemaker cells in sinoatrial node of rabbits. RESULTS Resveratrol (30-120 μmol·L-1) significantly decreased amplitude of action potential, maximal rate of depolarization (Vmax), velocity of diastolic (phase 4) depolarization and rate of pacemaker firing, but did not affect maximal diastolic potential and duration of 90% repolarization of action potential. Pretreatment with L-type calcium channel agonist Bay-K-8644 (0.5 μmol·L-1) 10 min antagonized the effect of resveratrol (60 μmol·L-1). While applying cesium chloride (2 mmol·L-1), a hyperpolarization-activated current blocker, adding tetraethylammonium chloride (20 mmol·L-1), a potassium channel antagonist, or applying L-NAME (0.5 mmol·L-1), a NO synthase inhibitor, had no significantly influence on the electrophysiological effects of resveratrol. CONCLUSION Resveratrol exerts inhibitory electrophysiological effects on pacemaker cells in sinoatrial node of rabbits, which may be due to reduction in calcium influx via a NO-independent manner.