Apomorphine and haloperidol-induced effects on male rat sexual behavior: no evidence for actions due to stimulation of central dopamine autoreceptors.

The administration of apomorphine (0.2-0.8 mg/kg IP) or (+)3-PPP(4-8 mg/kg IP) produced a facilitation of the male rat sexual behavior. Apomorphine in lower doses, as well as the selective DA autoreceptor agonist (-)3-PPP were ineffective. Except for a decrease in number of intromissions and an increase in the postejaculatory interval at the highest dose (0.32 mg/kg IP) there were no effects after administration of haloperidol. These data indicate that activation or inhibition of the presynaptic dopamine receptor does not affect male rat sexual behavior.