title: Role of vagus in the antagonism of ouabain induced arrhythmias in dogs by beta-adrenoceptor antagonists and related drugs.
abstract: The effects of propranolol and related drugs were investigated on ouabain-induced ventricular tachycardia (VT) in dogs with intact and ablated vagi. Propranolol and UM-272 completely antagonized the ouabain VT in dogs with intact vagi, whereas timolol was ineffective. Bilateral vagotomy completely abolished the effect of UM-272 and reduced the effect of propranolol. Diphenylhydantoin, however, reversed ouabain VT in dogs with both intact and ablated vagi. It is inferred that the vagus plays a significant role in the arrhythmolytic effect of propranolol and UM-272.
mesh_terms: D000319:Adrenergic beta-Antagonists / Q000494:pharmacology*; D000818:Animals; D000889:Anti-Arrhythmia Agents / Q000494:pharmacology; D001145:Arrhythmias, Cardiac / Q000139:chemically induced* / Q000503:physiopathology; D001794:Blood Pressure / Q000187:drug effects; D004285:Dogs; D005260:Female; D006339:Heart Rate / Q000187:drug effects; D006352:Heart Ventricles / Q000503:physiopathology; D008297:Male; D010042:Ouabain / Q000037:antagonists & inhibitors* / Q000633:toxicity; D010672:Phenytoin / Q000494:pharmacology; D011433:Propranolol / Q000031:analogs & derivatives / Q000494:pharmacology; D013610:Tachycardia / Q000139:chemically induced / Q000503:physiopathology; D013999:Timolol / Q000494:pharmacology; D014628:Vagotomy; D014630:Vagus Nerve / Q000502:physiology*
chemical_list: D000319:Adrenergic beta-Antagonists; D000889:Anti-Arrhythmia Agents; D010042:Ouabain; D010672:Phenytoin; C002616:pranolium; D013999:Timolol; D011433:Propranolol