L.: Pharmacological characterization of the discriminative stimulus (DS) effects of cocaine in rhesus monkeys. Psychopharmacology 96: S31

Rhesus monkeys (n = 6), trained in a two-lever, food-reinforced paradigm to discriminate cocaine (0.2 or 0.4 mg/kg, i.m.) from saline, received injections of cocaine (0.025-0.40 mg/kg, i.v. or i.m.) or various direct and indirect acting agonists (i.v.). Admin-istration of cocaine resulted in a dose-related increase in the percentage of responses that occurred on the drug-appropriate lever. The indirect dopamine agonists GBR 1 2909 (0.2-1.6 mgI kg), mazindol (0.025-0.4 mg/kg), nomifensine (0.025-0.2 mgI kg) and bupropion (0.1-1.6 mg/kg) each produced dose-related increases in cocaine-appropriate responding, with complete sub-stitution for cocaine achieved at the highest doses of each drug. In contrast, the norepinephnne re-uptake blockers tomoxetine (0.8-6.4 mg/kg) and nisoxetine (0.4-1.6 mg/kg), the serotonin re-uptake blocker fluoxetine (1.6-1 2.8 mg/kg), the D1 agonis