Specific GABA binding in the adrenals and blood corticosteroid levels in stress in intact rats and rats with changes in the functional activity of the hypothalamo-pituitary-adrenal system.

Thirty minutes of swimming led to decreases in the specific binding of GABA to adrenal plasma membranes in intact rats, but not in rats repeatedly given hydrocortisone to inhibit the baseline activity of the hypothalamic-pituitary-adrenal cortex system, where the level of reception of this amino acid was significantly greater than in controls. Pre-stress administration of baclofen and gamma-L-aminobutyryltaurine had no effect on specific GABA binding, even though these agents affected blood corticosterone concentrations.