COPULATION INCREASES DOPAMINE ACTIVITY IN THE MEDIAL PREOPTIC AREA OF MALE-RATS

Dopamine (DA) metabolites in microdialysates from the medial preoptic area (MPOA) of male rats increased during copulation. These increases were not observed during eating of a highly palatable food, or if the animal failed to copulate, or if the microdialysis probe was anterior or dorsal to the MPOA. The only two animals with measurable serotonin (5-HT) levels while the female was present were also the only two that either failed to copulate or copulated but failed to ejaculate. These data are consistent with previous evidence for a facilitative role of MPOA DA in the control of male sexual behavior; however, 5-HT activity in the MPOA may impair copulation.