DIFFERENTIAL EFFECT OF CHRONIC ETHANOL TREATMENT ON BARBITURATE AND STEROID MODULATION OF MUSCIMOL-BINDING TO RAT-BRAIN CORTEX

We report the differential alterations produced by chronic ethanol tre atment on the modulation, by the barbiturate thiopental and the steroi d 5beta-pregnan-3alpha-ol-20-one, of the binding of [H-3]muscimol to m embrane preparations from rat brain cortex. We found a clear barbitura te- and steroid-promoted enhancement of muscimol-binding to membranes in both control and ethanol-treated animals. However, the enhancements were higher in control animals, using the barbiturate, and in ethanol -treated rats, using the steroid. B(max) and K(d) values were also dif ferentially affected in control and ethanol-treated animals by the pre sence of the barbiturate or the steroid.