GABAergic control of masculine sexual behavior.

Drugs affecting the GABAergic transmission were injected into the medial preoptic anterior hypothalamic area (MPOA) and the masculine sexual behavior analyzed. Antagonizing GABAergic neurotransmission by (+) bicuculline methiodide (30 ng/cannula), or 3-mercaptopropionic acid (10 or 20 micrograms/cannula) resulted in a drastic shortening of the postejaculatory intervals and a shortening of the ejaculation latency. Injection of compounds causing an increase in GABAergic activity, muscimol (25 ng/cannula) or ethanolamine-O-sulphate (80 micrograms/cannula) depressed masculine sexual behavior. Systemic treatment or injection into the nucleus caudatus putamen of compounds affecting the GABAergic transmission did not cause any alteration in the mating pattern. It is suggested that the GABAergic neurotransmission is involved in inhibitory processes underlying the masculine sexual behavior.