Effect of SB-277011A on cocaine self-administration under an FR10 reinforcement schedule for unit cocaine reinforcement infusions of 0.125, 0.25 or 0.5 mg/kg/infusion. (A) Representative event records of cocaine infusions (each vertical line represents an earned 0.5 mg/kg cocaine infusion under FR10 reinforcement conditions), illustrating a typical pattern of extinction responding after systemic SB-277011A (24 mg/kg, i.p.) administration. (B) Time courses of cocaine (0.25 mg/kg/infusion) self-administration after pretreatment with either the vehicle (25% 2-hydroxypropyl-β-cyclodextrin) or 24 mg/kg SB-277011A. (C) Mean number of infusions (± SEM, n = 7) during the 3-h session after administration of the vehicle or SB-277011A (24 mg/kg, i.p.) 1 h prior to the test session. *P < 0.05, **P < 0.01, ***P < 0.001; individual group comparisons using the Tukey (a) statistic, when compared with the vehicle treatment group (see more statistical details in the Results section).