The sympathomimetic activity of N-isopropyloctopamine in vitro.
Isolated right and left guinea-pig atria, guinea-pig tracheae and rabbit aortic strips were used to define the sympathomimetic properties of N-isopropyloctopamine. This compound was a highly beta selective, direct-acting adrenergic agonist, approximately 200- and 440-fold less potent than isoproterenol in cardiac and smooth muscle, respectively. It was nearly a full agonist in both cardiac and smooth muscle without appreciable selectivity for either beta-1 or beta-2 receptors and had no demonstrable beta blocking activity. No alpha adrenergic activity was detectable within the concentration range tested. The chronotropic effect of N-isopropyloctopamine was very persistent and resistant to repeated washing of the tissues, which may reflect unusually firm binding to beta receptors.
D000818:Animals; D001011:Aorta / Q000187:drug effects / Q000502:physiology; D016275:Atrial Function; D001681:Biological Assay; D000242:Cyclic AMP / Q000378:metabolism; D006168:Guinea Pigs; D006325:Heart Atria / Q000187:drug effects; D007545:Isoproterenol / Q000494:pharmacology; D008297:Male; D009119:Muscle Contraction / Q000187:drug effects*; D009655:Octopamine / Q000031:analogs & derivatives* / Q000494:pharmacology; D010656:Phenylephrine / Q000494:pharmacology; D011433:Propranolol / Q000494:pharmacology; D011817:Rabbits; D012110:Reserpine / Q000494:pharmacology; D013566:Sympathomimetics / Q000494:pharmacology*; D014132:Trachea / Q000187:drug effects / Q000502:physiology
D013566:Sympathomimetics; D009655:Octopamine; D010656:Phenylephrine; D012110:Reserpine; D011433:Propranolol; C001416:deterenol; D000242:Cyclic AMP; D007545:Isoproterenol