Evaluation of the reinforcing and discriminative stimulus effects of gamma-hydroxybutyrate in rhesus monkeys
Woolverton WL, Rowlett JK, Winger G,
Woods JH, Gerak LR, France CP
Department of Psychiatry and Human Behavior,
University of Mississippi Medical Center,
Jackson 39216, USA.
Drug Alcohol Depend 1999 Apr 1; 54(2):137-43
Gamma-hydroxybutyrate (GHB) is a metabolite of GABA that is present in the CNS and fulfils at least some of the criteria for a neurotransmitter. Its effects are generally similar to those of CNS depressants and include ataxia, sleep and anesthesia. It has also been suggested that GHB is a drug of abuse. The present experiment was designed to evaluate GHB in procedures predictive of abuse and dependence potential in rhesus monkeys. Three monkeys were surgically prepared with indwelling silicone venous catheters and allowed to self-administer methohexital or saline in twice-daily experimental sessions. Other groups of monkeys were trained in drug discrimination paradigms to discriminate D-amphetamine (AMPH; n = 4), pentobarbital (PB; n = 3) or triazolam (n = 3) from saline. Another group was maintained on diazepam daily and trained to discriminate flumazenil from saline (n = 2). GHB (0.01-10 mg/kg per injection) maintained self-administration marginally above saline levels at one dose (3.2 or 10 mg/kg) in two of the three monkeys tested. GHB (1.0-178 mg/kg, subcutaneously (