The affinity of bopindolol and its two metabolites for a beta 2-adrenoceptor in the bovine mesenteric artery.
Bopindolol and its two metabolites (18-502 and 20-785) were examined for their affinity to a beta 2-adrenoceptor in the bovine mesenteric artery using the radioligand binding assay method with [3H]CGP12177 as a radioligand. The Scatchard analysis of the data demonstrated a uniphasic plot with Kd and Bmax values of 0.86 +/- 0.16 nM, and 13.34 +/- 1.11 fmol/mg protein, respectively. The pKi values of bopindolol and its two metabolites for beta 2-adrenoceptors in the bovine mesenteric artery were 7.70 +/- 0.13, 8.07 +/- 0.13, 8.20 +/- 0.24, respectively, with 20-785 showing the highest values among these drugs. The present findings indicate that the bovine mesenteric artery membrane is predominantly beta 2-adrenoceptor tissue, and that bopindolol and its two metabolites were potent for beta 2-adrenoceptors in the bovine mesenteric artery.
Hosohata
Y
Y
Department of Pharmacology, Niigata College of Pharmacy, Japan.
Suzuki
M
M
Karakisawa
Y
Y
Maruyama
K
K
Nagatomo
T
T
D000319:Adrenergic beta-Antagonists / Q000493:pharmacokinetics*; D000818:Animals; D002417:Cattle; D066298:In Vitro Techniques; D008638:Mesenteric Arteries / Q000378:metabolism; D009131:Muscle, Smooth, Vascular / Q000378:metabolism*; D010869:Pindolol / Q000031:analogs & derivatives* / Q000493:pharmacokinetics; D011412:Propanolamines / Q000493:pharmacokinetics; D011869:Radioligand Assay; D018343:Receptors, Adrenergic, beta-2 / Q000378:metabolism*
D000319:Adrenergic beta-Antagonists; D011412:Propanolamines; D018343:Receptors, Adrenergic, beta-2; D010869:Pindolol; C036007:bopindolol; C033394:CGP 12177