Characterization of FR173657, a novel nonpeptide B2 antagonist: in vitro and in vivo studies.
Bradykinin (BK) is involved in different pathophysiological conditions, including allergic and (or) inflammatory reactions. Thus, BK antagonists are considered as a potential drug in allergic and (or) inflammatory diseases. Orally active BK antagonist would be desirable for this purpose. Here, we describe the pharmacological characterization of FR173657 ((E)-3-(6-acetamido-3-pyridyl)-N-[N-[2,4-dichloro-3-[(2-methyl-8- quinolinyl)oxymethyl]phenyl]-N-methylaminocarbonylmethyl]acr ylamide) obtained from our screening for nonpeptide, orally active B2 antagonists. (i) FR173657 antagonized [3H]BK binding with IC50 values of 4.6 x 10(-10) and 8.6 x 10(-9) M in membrane preparations of guinea pig ileum and lung, respectively. FR173657 inhibited [3H]BK binding to A431, W138, and IMR90 cell lines of human origin with IC50 values of 2.0 x 10(-9), 2.3 x 10(-9), and 1.7 x 10(-9) M, respectively. FR173657 did not affect [3H]des-Arg10-kallidin (B1 ligand) binding onto IMR90 cells. (ii) FR173657 inhibited guinea pig ileum contractions by BK (6 x 10(-8) M) with an IC50 value of 6.1 x 10(-9) M. Acetylcholine- and histamine-induced contraction of guinea pig ileum was unaffected by FR173657. (iii) Oral administration of FR173657 dose-dependently inhibited BK (5 micrograms/kg) and dextran sulfate (activator of kinin-kallikrein cascade) induced bronchoconstriction with ED50 values of 0.075 and 0.057 mg/kg, respectively. In conclusion, FR173657 is a selective potent, orally active B2 receptor antagonist that can be used to investigate the role of BK in allergic and inflammatory diseases.
Inamura
N
N
Drug Discovery Division, Fujisawa Pharmaceutical Co. Ltd., Osaka, Japan.
Asano
M
M
Kayakiri
H
H
Hatori
C
C
Oku
T
T
Nakahara
K
K
D000284:Administration, Oral; D000818:Animals; D001920:Bradykinin / Q000378:metabolism; D065168:Bradykinin Receptor Antagonists; D016084:Bronchoconstriction / Q000187:drug effects; D002478:Cells, Cultured; D004347:Drug Interactions; D006168:Guinea Pigs; D006801:Humans; D007082:Ileum / Q000187:drug effects / Q000378:metabolism / Q000648:ultrastructure; D066298:In Vitro Techniques; D008168:Lung / Q000187:drug effects / Q000378:metabolism / Q000648:ultrastructure; D008297:Male; D008566:Membranes / Q000187:drug effects / Q000378:metabolism / Q000648:ultrastructure; D009119:Muscle Contraction / Q000187:drug effects; D011804:Quinolines / Q000494:pharmacology*; D043782:Receptor, Bradykinin B2; D018002:Receptors, Bradykinin / Q000378:metabolism; D014316:Tritium
D065168:Bradykinin Receptor Antagonists; C105311:FR 173657; D011804:Quinolines; D043782:Receptor, Bradykinin B2; D018002:Receptors, Bradykinin; D014316:Tritium; D001920:Bradykinin