title: In vitro inhibitory effect of SR 27417, a potent platelet-activating factor (PAF) receptor antagonist, on the PAF-induced bovine platelet aggregation.
abstract: The in vitro inhibitory effect of SR 27417, an antagonist of the platelet-activating factor (PAF) receptor, on PAF-induced platelet aggregation was studied in blood collected from seven healthy Friesien calves. Inhibitory effects of SR 27417 were determined at thirteen different concentrations (0.1-400 nM) by using the dose-response curves of PAF on calf platelet aggregation. In the presence of SR 27417, the maximal slopes of aggregation (%/min) induced by low and high concentrations of PAF were significantly different from the control values obtained without an antagonist at p < or = 0.05 and p < or = 0.01 respectively. In vitro PAF-induced calf platelet aggregation was dose-dependently inhibited by SR 27417. The drug inhibited PAF-induced platelet aggregation in a competitive reversible manner (pA2 = 10.46 +/- 2.36 mol x L(-1)). In conclusion, the results of our study showed that addition of SR 27417 to bovine platelet in vitro inhibits PAF-induced platelet aggregation.
authors.affiliation: Département de physiologie, Faculté de Médecine Vétérinaire, Université de Liège, Sart Tilman, Belgium.
authors.forename: M
authors.initials: M
authors.lastname: Bastos da Silva
authors.forename: A
authors.initials: A
authors.lastname: Delaunois
authors.forename: P
authors.initials: P
authors.lastname: Gustin
authors.forename: J M
authors.initials: JM
authors.lastname: Godeau
authors.forename: P
authors.initials: P
authors.lastname: Lekeux
mesh_terms: D000818:Animals; D002417:Cattle / Q000097:blood*; D002478:Cells, Cultured; D004305:Dose-Response Relationship, Drug; D010972:Platelet Activating Factor / Q000008:administration & dosage / Q000494:pharmacology*; D010974:Platelet Aggregation / Q000187:drug effects*; D010980:Platelet Membrane Glycoproteins / Q000037:antagonists & inhibitors*; D011956:Receptors, Cell Surface; D043562:Receptors, G-Protein-Coupled; D013844:Thiazoles / Q000494:pharmacology*
chemical_list: D010972:Platelet Activating Factor; D010980:Platelet Membrane Glycoproteins; D011956:Receptors, Cell Surface; D043562:Receptors, G-Protein-Coupled; D013844:Thiazoles; C039351:platelet activating factor receptor; C071317:Foropafant