The influence of haloperidol and aminooxyacetic acid on etonitazene, alcohol, diazepam and barbital consumption.

Four groups of rats were given free choice between water and solutions of either 3 micrograms/ml etonitazene, 5% ethanol (v/v), 0.1 mg/ml diazepam or 3 mg/ml barbital for 10-14 days. With the exception of barbital, some rats spontaneously preferred the drug solutions to water. This preference was reduced by addition of 7 micrograms/ml haolperidol. In a forced drug fluid consumption procedure, the daily administration of 15 mg/kg i.p. of the gamma-aminobutyric acid (GABA)-transaminase blocker aminooxyacetic acid (AOAA) led to a reduction of ethanol and diazepam intake, but not of etonitazene and barbital. It is suggested that the diminished consumption of ethanol and diazepam as caused by GABA-T-inhibition may also be mediated by dopamine which seems to act indirectly, via benzodiazepine receptors and GABA neurons.