Sch412348

Sch412348 is a potent competitive antagonist of the human adenosine A_2A receptor (K_i=0.6 nM) and has >1000-fold selectivity over all other adenosine receptors. IC50 & Target: Ki: 0.6 nM (Adenosine A_2A receptor)^[1] In Vitro: Sch412348 (SCH 412348) also completely antagonizes cAMP in cells expressing the recombinant human A_2A receptor. Sch412348 is determined to have K_B values of 0.3 nM, respectively at the A_2A receptor; the value are in good agreement with the K_i values determined in radioligand binding assays. A similar functional assay with A_2B receptor-expressing cells is used to demonstrate selectivity over A_2B receptors. In this assay, the K_B value for Sch412348 is 273 nM, indicating that Sch412348 is 910-fold selective for the A_2A receptor over the A_2B receptor^[1]. In Vivo: Oral administration of Sch412348 (0.1-1 mg/kg) to rats potentiates 3,4-dihydroxy-L-phenylalanine (L-Dopa)-induced contralateral rotations after 6-hydroxydopamine lesions in the medial forebrain bundle and potently attenuates the cataleptic effects of haloperidol. Sch412348 (1 and 3 mg/kg) dose-dependently attenuates haloperidol-induced catalepsy 1 h [F(3,20)=3.9, p<0.05] and 4 h [F(3,20)=7.5, p<0.01] after dosing. Sch412348 [F(2,51) =10.6, p<0.01] (0.1-1 mg/kg) reduces immobility time in the mouse tail suspension test (TST) at 1 mg/kg. Sch412348 (SCH 412348) significantly increases activity levels in the mouse [F(4,27)=2.9, p<0.05]. Both the 0.3 and 3 mg/kg treatment groups are significantly more active than vehicle-treated mice. The 1 mg/kg group approached significance (p=0.052)^[1].