The effects of stimulants and depressants on cocaine self-administration behavior in the Rhesus monkey

Abstract

The effects of acute intramuscular pretreatment with several dosages of a variety of centrally acting compounds on intravenous cocaine self-administration behavior were ascertained. Pretreatment with morphine and pentobarbital produced no change in this behavior until dosages (2.0 mg/kg and 15.0 mg/kg respectively) were administered which grossly depressed grooming, exploratory, and locomotor activity behaviors, d -amphetamine (0.5–4.0 mg/kg) and phenmetrazine (2.0–12.0 mg/kg) pretreatment produced a dose-related decrease in cocaine self-administration. Trifluoperazine in dosages of 0.01–0.1 mg/kg increased the frequency of this behavior; whereas, higher dosages (0.2, 0.4 mg/kg) grossly depressed behavior. Imipramine (10–50 mg/kg) produced a dose-related decrease in cocaine self-administration. Potential mechanisms of these drug—behavior and drug—drug interactions are discussed.