title: Functional evidence against the existence of beta 2-adrenoceptors mediating positive intropic effects in guinea-pig right ventricular myocardium.
abstract: In guinea-pig isolated papillary muscles we studied the positive inotropic effects of the beta-adrenoceptor agonists isoprenaline, fenoterol and noradrenaline in the presence and absence of the beta 1-selective antagonist atenolol and the beta 2-adrenoceptor antagonist ICI 118.551. In Schild regression analysis pA2 values, for either atenolol (7.14-7.16) and ICI 118.551 (6.79-6.84) were independent of the agonists used. These results support the view that the inotropic response in guinea-pig ventricular myocardium is mediated by beta 1-adrenoceptors only.
authors.affiliation: Division of Cardiology, Hannover Medical School, Germany.
authors.forename: A
authors.initials: A
authors.lastname: Mügge
authors.forename: J
authors.initials: J
authors.lastname: Oldenburg
authors.forename: W
authors.initials: W
authors.lastname: Schmitz
authors.forename: H
authors.initials: H
authors.lastname: Scholz
mesh_terms: D000818:Animals; D001262:Atenolol / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D006168:Guinea Pigs; D066298:In Vitro Techniques; D009200:Myocardial Contraction / Q000187:drug effects*; D010210:Papillary Muscles / Q000187:drug effects / Q000502:physiology; D011412:Propanolamines / Q000494:pharmacology; D018343:Receptors, Adrenergic, beta-2 / Q000502:physiology*
chemical_list: D011412:Propanolamines; D018343:Receptors, Adrenergic, beta-2; C026777:ICI 118551; D001262:Atenolol