title: Inotropic responses of isolated atrial and ventricular muscle from the dog heart to inosine, guanosine and adenosine.
abstract: 1. The inotropic effects of inosine, adenosine and guanosine were compared in isolated and blood-perfused canine atrial and ventricular muscle preparations paced at 1.5-2.5 Hz. 2. In isolated atria, guanosine and inosine usually had positive inotropic effects, but adenosine consistently had a marked negative inotropic effect. 3. In ventricular muscles, the three purine compounds examined produced dose-related positive inotropic responses, but adenosine also produced a slight negative inotropic response which preceded the positive inotropic response.
mesh_terms: D000241:Adenosine / Q000494:pharmacology*; D000818:Animals; D004285:Dogs; D004305:Dose-Response Relationship, Drug; D006151:Guanosine / Q000494:pharmacology*; D066298:In Vitro Techniques; D007288:Inosine / Q000494:pharmacology*; D009200:Myocardial Contraction / Q000187:drug effects*
chemical_list: D006151:Guanosine; D007288:Inosine; D000241:Adenosine