Table 1.

Heroin self-administration subgroups and corresponding treatment

Day 1 Treatment		Second Test Treatment		Third Test Treatment
First Subgroup	Second Subgroup	First Subgroup	Second Subgroup	First Subgroup	Second Subgroup
Vehicle + cue-induced reinstatement	SA-57 (1 mg/kg) + cue-induced reinstatement	Vehicle + cue-induced reinstatement	SA-57 (2.5 mg/kg) + cue-induced reinstatement	Vehicle + cue-induced reinstatement	SA-57 (5 mg/kg) + cue-induced reinstatement