INCREASED EXTRACELLULAR DOPAMINE IN THE NUCLEUS-ACCUMBENS AND STRIATUM OF THE FEMALE RAT DURING PACED COPULATORY-BEHAVIOR

Five groups of ovariectomized rats were tested during in vivo microdia lysis, and concentrations of dopamine (DA) and its metabolites were de termined in dialysate. in striatum, DA increased more in hormone-prime d ovariectomized female rats pacing copulation than in those engaging in sex that could not pace, those that were hormone primed but tested without a male present, or oil-treated groups (p < .02). Administratio n of estrogen before microdialysis resulted in enhanced striatal DA in response to a male rat relative to the animals tested without a male (p < .06). Female rats that were pacing sexual behavior also exhibited a greater increase in accumbens DA than did the no-male, estrogen-pri med, or oil-treated groups (p < .015). Nonpacing animals displayed a s ignificant decrease in DA from accumbens 30 min after introduction of the male rat (p < .05) but otherwise were not different from pacing an imals. Estrogen-treated animals also had an enhanced increase in accum bens DA compared with oil-treated rats (p < .05). These data suggest t hat DA release in the striatum and accumbens is dependent on the conte xt in which sexual behavior occurs and that estrogen may in part modul ate these dopaminergic responses.