High affinity of carazolol for β-adrenoceptors coupled to the adenylyl cyclase in ventricular myocardium of kitten and xenopus laevis

Abstract
Summary Catecholamine-induced stimulation of adenylyl cyclase in ventricular membranes of kitten and Xenopus laevis was antagonized competitively by carazolol. Apparent equilibrium constants ranging between 100–170 pM were estimated for the β-adrenoceptorcarazolol complex.