THE EFFECTS OF ACUTE AND CHRONIC ETHANOL ADMINISTRATION AND ITS WITHDRAWAL ON γ‐AMINOBUTYRIC ACID RECEPTOR BINDING IN RAT BRAIN

The effects of acute and chronic ethanol administration, and withdrawal on the binding of the inhibitory neurotransmitter, γ‐aminobutyric acid (GABA), was investigated in rat brain. Acute ethanol (2 to 4 g/kg i.p. 30 min before removal of brain) produced an increase in the binding capacity of the low affinity GABA receptor binding site. Following chronic ethanol administration (1 to 21 days), the GABA receptor binding characteristics were not altered. These results suggest a possible adaptation of GABA receptors to the continuous presence of ethanol at the GABA synapse. During ethanol withdrawal, the affinity of the low affinity GABA receptor binding site was significantly lower than pair‐fed controls at 8 and 16 h withdrawal. These results suggest that GABA receptor sensitivity may play a role in some of the neuropharmacological effects of ethanol and in its withdrawal symptoms. 1980 British Pharmacological Society