title: Positive chronotropic and negative inotropic actions of vasopressin in isolated blood-perfused canine atrium.
abstract: Effects of vasopressin on SA nodal pacemaker activity and atrial contractility were investigated, using 5 isolated, blood-perfused canine atrium preparations. Vasopressin produced a dose-related positive chronotropic and negative inotropic effect, which was not influenced by treatments with an adequate dose of atropine or an adrenergic beta-blocking agent, alprenolol. From these results, it is concluded that vasopressin has a direct stimulating property on SA nodal pacemaker activity and a direct suppressive property on atrial contractility.
mesh_terms: D000109:Acetylcholine / Q000494:pharmacology; D000526:Alprenolol / Q000494:pharmacology; D000818:Animals; D016275:Atrial Function; D001285:Atropine / Q000494:pharmacology; D001769:Blood; D004285:Dogs; D004305:Dose-Response Relationship, Drug; D006325:Heart Atria / Q000187:drug effects; D006339:Heart Rate / Q000187:drug effects*; D009200:Myocardial Contraction / Q000187:drug effects*; D009638:Norepinephrine / Q000494:pharmacology; D012849:Sinoatrial Node / Q000187:drug effects; D014667:Vasopressins / Q000494:pharmacology*
chemical_list: D014667:Vasopressins; D001285:Atropine; D000526:Alprenolol; D000109:Acetylcholine; D009638:Norepinephrine