SR 146131 is a potent, orally available, and selective nonpeptide ( cholecystokinin 1 ) receptor agonist. In Vitro SR 146131 inhibits in the binding of [ 125 I]-BH-CCK-8S to CCK1sites on 3T3-hCCK1 cell membranes with an IC 50 value of 0.56 ± 0.10 nM. At much higher concentrations, SR 146131 also inhibits the binding of radiolabeled CCK to CCK2sites in CHO-hCCK2 membranes with an IC 50 of 162 ± 27 nM. SR 146131 is a potent CCK1 agonist on several intracellular events linked to CCK1 receptor activation in various cell types: on [Ca 2+ ]i release and IP1 formation, SR 146131 appears as a full CCK1 receptor agonist in the 3T3-hCCK1 cells, but a partial CCK1receptor agonist on MAPK activation and early gene expression in this cell line. SR 146131 also acts as a partial agonist in the two neuroblastoma cell lines. MCE has not independently confirmed the accuracy of these methods. They are for reference only. In Vivo SR 146131 completely inhibits gastric and gallbladder emptying in mice (ED 50 of 66 and 2.7 μg/kg p.o., respectively). SR 146131 dose dependently reduces food intake in fasted rats (from 0.1 mg/kg p.o.), in nonfasted rats in which food intake has been highly stimulated by the administration of neuropeptide Y (1–36) (from 0.3 mg/kg p.o.), in fasted gerbils (from 0.1 mg/kg p.o.), and in marmosets maintained on a restricted diet (from 3 mg/kg p.o.). SR 146131 (10 mg/kg p.o.) also increases the number of Fos-positive cells in the hypothalamic paraventricular nucleus of rats. Locomotor activity of mice is reduced by orally administered SR 146131 (from 0.3 mg/kg p.o.) . MCE has not independently confirmed the accuracy of these methods. They are for reference only. Form:Solid IC50& Target:Cholecystokinin 1 receptor