[Nα-Bodipy]-des-Arg9-BK affinity for B
R was evaluated by quantitative autoradiography. Increasing concentration (10-10 to 10-6 M) of Hoe 140 (selective B2R antagonist) displaced total binding of 200 pM [125I]-HPP-HOE-140 to B2R. In contrast, same concentrations of [Nα-Bodipy]-des-Arg9-BK (fluorescent B1R agonist) did not displace the B2R radioligand. Data are means ± SEM of 4 sections per rat from 7 different rats for each compound.