title: Antiarrhythmic effects of coronary vasodilators on canine ventricular arrhythmia models.
abstract: Antiarrhythmic effects of intravenous coronary vasodilators (verapamil, diltiazem, bepridil, trimetazidine and nicorandil) were evaluated using two canine ventricular arrhythmia models (halothane-adrenaline arrhythmia and digitalis arrhythmia), and the minimum effective plasma concentrations of the drugs were determined for each arrhythmia model. Verapamil (0.1 mg/kg), diltiazem (0.1 mg/kg), bepridil (1 mg/kg) and high dose trimetazidine (10 mg/kg) were effective on halothane-adrenaline arrhythmia; and the minimum effective plasma concentrations of the above drugs were less than 30 +/- 10 ng/ml, less than 18 +/- 5 ng/ml, 0.38 +/- 0.11 microgram/ml and 7.0 +/- 1.5 micrograms/ml, respectively. Nicorandil (1 mg/kg) did not suppress halothane-adrenaline arrhythmia. Verapamil, diltiazem and bepridil must have suppressed the halothane-adrenaline arrhythmia by blocking the Ca channel. Verapamil (1 mg/kg), diltiazem (1 mg/kg), bepridil (5 mg/kg), trimetazidine (3 mg/kg) and nicorandil (3 mg/kg) were ineffective on digitalis arrhythmia, even though their maximum hypotensive doses were used.
mesh_terms: D000818:Animals; D000889:Anti-Arrhythmia Agents; D001145:Arrhythmias, Cardiac / Q000139:chemically induced / Q000188:drug therapy; D001794:Blood Pressure / Q000187:drug effects; D004071:Digitalis Glycosides; D004285:Dogs; D004837:Epinephrine; D005260:Female; D006221:Halothane; D006339:Heart Rate / Q000187:drug effects; D008297:Male; D014665:Vasodilator Agents / Q000097:blood / Q000494:pharmacology*
chemical_list: D000889:Anti-Arrhythmia Agents; D004071:Digitalis Glycosides; D014665:Vasodilator Agents; D006221:Halothane; D004837:Epinephrine