title: Effects of vagotomy and drugs on the ventricular fibrillation threshold of normal and ischemic hearts in the anesthetized rat.
abstract: The ventricular fibrillation threshold (VFT) was determined by the electrical stimulation of the normal and the coronary artery-ligated myocardium in situ in anesthetized rats. A bilateral vagotomy lowered the VFT of the normal myocardium. After the coronary artery ligation in the vagotomized rats, VFT fell to a greater extent. Bretylium 20-40 mg/kg i.v. produced an elevation of VFT, hypotension and a decrease of the heart rate of rats with the normal or the ischemic myocardium. Lidocaine 10 mg/kg i.v. insignificantly affected the VFT of the normal and the ischemic myocardium. Nitroprusside 4 mg/kg i.v. elevated the VFT of the normal myocardium, and prevented a fall in the VFT of the ischemic myocardium. Adenosine 10 mg/kg or aspirin 20 mg/kg i.v. had no remarkable effect on the VFT of the normal myocardium, but prevented a fall in the VFT of the ischemic myocardium.
mesh_terms: D000241:Adenosine / Q000494:pharmacology; D000758:Anesthesia; D000818:Animals; D001241:Aspirin / Q000494:pharmacology; D001794:Blood Pressure / Q000187:drug effects; D001949:Bretylium Compounds / Q000494:pharmacology; D003327:Coronary Disease / Q000503:physiopathology*; D006339:Heart Rate / Q000187:drug effects; D008012:Lidocaine / Q000494:pharmacology; D008297:Male; D009599:Nitroprusside / Q000494:pharmacology; D051381:Rats; D014628:Vagotomy; D014693:Ventricular Fibrillation / Q000503:physiopathology*
chemical_list: D001949:Bretylium Compounds; D009599:Nitroprusside; D008012:Lidocaine; D000241:Adenosine; D001241:Aspirin