[Possible mechanism of the activating action of GABA-positive substances]

The effects of high and low doses of GABA-positive drugs (muscimol, depakine) and a tranquillizer diazepam on behavioral and electrophysiological indices were studied. The depressant effect of high doses and the activating one of low doses of the studied agents were shown. It was concluded that the activating effect of GABA-positive drugs reflects the activity of the disinhibitory system, that is, the group of interneurons suppressing the activity of inhibitory neurons. GABA seems to be a transmitter in the disinhibitory system.