title: Haemodynamic effects of the quaternary ammonium compound QX 572 in anaesthetized cats. III. Interactions with adrenergic beta-adrenoceptor blockade.
abstract: The positive cardiac chronotropic effects of the antiarrhythmic compound, QX 572, in anaesthetized cats has been shown mainly to be due to a release of catecholamines from sympathetic nerve-endings. Furthermore, these undesired effects of QX 572 on heart rate were decreased by adrenergic beta blockade in the animals. In the present study it was found that an adrenergic beta-blockade did not reveal any cardiodepressive effects of QX 572, that in the normal animals might have been masked by the effects of the drug-induced catecholamine-release.
mesh_terms: D000319:Adrenergic beta-Antagonists; D000818:Animals; D000889:Anti-Arrhythmia Agents / Q000494:pharmacology*; D001794:Blood Pressure / Q000187:drug effects; D002415:Cats; D004347:Drug Interactions; D005260:Female; D006339:Heart Rate / Q000187:drug effects*; D007545:Isoproterenol / Q000494:pharmacology; D008297:Male; D008790:Metoprolol / Q000494:pharmacology; D000644:Quaternary Ammonium Compounds / Q000494:pharmacology*; D012965:Sodium Chloride / Q000494:pharmacology
chemical_list: D000319:Adrenergic beta-Antagonists; D000889:Anti-Arrhythmia Agents; D000644:Quaternary Ammonium Compounds; D012965:Sodium Chloride; D008790:Metoprolol; D007545:Isoproterenol