LF 16.0335, a novel potent and selective nonpeptide antagonist of the human bradykinin B2 receptor.
1. In the present paper, we describe the in vitro pharmacological properties of LF 16.0335 (1-[[3-[(2,4-dimethylquinolin-8-yl)oxymethyl]-2,4-dichloro-p henyl]sulphonyl] -2(S) - [[4 -[4-(aminoiminomethyl)phenylcarbonyl]piperazin-1-yl]ca rbonyl]pyrrolidine), a novel and potent nonpeptide antagonist of the human bradykinin (BK) B2 receptor. 2. LF 16.0335 displaced [3H]-BK binding to membrane preparations from CHO cells expressing the cloned human B2 receptor, INT 407 cells and human umbilical vein with Ki values of 0.84+/-0.39 nM, 1.26+/-0.68 nM and 2.34+/-0.36 nM, respectively. 3. In saturation binding studies performed in INT 407 cell membranes in the presence or absence of LF 16.0335, max values of [3H]-BK were not significantly changed suggesting that LF 16.0335 behaves as a competitive antagonist. 4. LF 16.0335 had no affinity for the cloned human kinin B1 receptor stably expressed in 293 cells. In addition, this compound at 1 microM did not significantly bind to a range of 40 different membrane receptors and eight ion channels except muscarinic M2 and M1 receptors for which an IC50 value of 0.9 and 1 microM was obtained. 5. BK stimulates in a concentration-dependent manner phosphoinositosides (IPs) production in cultured INT 407 cells. Concentration-response-curves to BK were shifted to the right in the presence of LF 16.0335 (0.1 microM) without reduction of the maximum. LF 16.0335 inhibited the concentration-contraction curve to BK in the human umbilical vein giving a pA2 value of 8.30+/-0.30 with a Schild plot slope that was not different from unity. 6. These results demonstrate that LF 16.0335 is a potent, selective and competitive antagonist of the human bradykinin B2 receptor.
Pruneau
D
D
Groupe de Pharmacochimie des Récepteurs, Centre de Recherche, Laboratoires Fournier, Daix, France.
Luccarini
J M
JM
Fouchet
C
C
Defrêne
E
E
Franck
R M
RM
Loillier
B
B
Duclos
H
H
Robert
C
C
Cremers
B
B
Bélichard
P
P
Paquet
J L
JL
D000578:Amidines / Q000737:chemistry / Q000494:pharmacology*; D001667:Binding, Competitive; D001920:Bradykinin / Q000494:pharmacology*; D065168:Bradykinin Receptor Antagonists; D002478:Cells, Cultured; D004305:Dose-Response Relationship, Drug; D006801:Humans; D066298:In Vitro Techniques; D010716:Phosphatidylinositols / Q000096:biosynthesis; D010879:Piperazines / Q000737:chemistry / Q000494:pharmacology*; D043782:Receptor, Bradykinin B2; D014471:Umbilical Veins / Q000187:drug effects / Q000378:metabolism; D014661:Vasoconstriction / Q000187:drug effects
D000578:Amidines; D065168:Bradykinin Receptor Antagonists; C116248:LF 16.0335; D010716:Phosphatidylinositols; D010879:Piperazines; D043782:Receptor, Bradykinin B2; D001920:Bradykinin