Effect of gallic acid on electrophysiological properties and ventricular arrhythmia following chemical-induced arrhythmia in rat

Objective(s): Ventricular arrhythmias including ventricular tachycardia (VT) and ventricular fibrillation (VF) are the most important causes of mortality rate. Gallic acid (GA) has beneficial effects on cardiovascular diseases. The aim of this study was to evaluate the effects of GA on electrophysiological parameters such as QRS complex, heart rate (HR), PR interval parameters, and ventricular arrhythmia following chemical induction in rat. Materials and Methods: Seventy-two male rats were divided into 9 groups (n=8). Chronic groups pretreated by GA (10, 30, and 50 mg/kg, orally) and normal saline (N/S, 1 ml/kg, orally) for 10 days. At the start of the experiments (the first day) and on the final day of the experiments (tenth day), the electrocardiogram (lead II) was recorded. At acute group, GA (50 mg/kg), and anti-arrhythmic drugs such as propranolol, amiodarone, and verapamil injected via intravenous (IV). Then, arrhythmia induced by a CaCl2 2.5% solution (140 mg/kg, IV). Afterward, percentage of premature ventricular beats (PVB), VF, and VT were recorded at 1, and 3 min. Results: These findings showed that chronic and acute doses of GA have positive inotropic and antidysrhythmic effects by significant reduction of PVB, VT and VF on comparison with the control group. These actions are comparable to anti-arrhythmic drugs such as quinidine, propranolol, amiodarone, and verapamil. GA has not significant effect on chronotropic and dromotropic properties. Conclusion: Findings showed that GA has antiarrhythmic, and inotropic characteristics that suggested GA has effective for mild congestive heart failure, and cardiovascular disorders patients which susceptible to incidence of arrhythmias.