A D1 agonist in the MPOA facilitates copulation in male rats.
The classic dopamine agonist apomorphine, microinjected into the medial preoptic area (MPOA), enhances the copulatory behavior of male rats, while pharmacological blockade of endogenous dopamine inhibits sexual behavior. We now report that MPOA injections of 10 micrograms of the selective D1 agonist dihydroxyphenyl-tetrahydrothienopyridine (THP) significantly increased the number of ejaculations, while decreasing the latency to ejaculate in a 30-min test. These effects were not observed following coadministration of the selective D1 antagonist SCH-23390 with 10 micrograms THP. This enhancement may be related to a D1-stimulated facilitation of penile erections.
Markowski
V P
VP
Department of Psychology, State University of New York at Buffalo 14260.
Eaton
R C
RC
Lumley
L A
LA
Moses
J
J
Hull
E M
EM
D000818:Animals; D001058:Apomorphine / Q000008:administration & dosage / Q000494:pharmacology; D001552:Benzazepines / Q000008:administration & dosage / Q000494:pharmacology; D003307:Copulation / Q000187:drug effects*; D015259:Dopamine Agents / Q000008:administration & dosage / Q000494:pharmacology*; D004542:Ejaculation / Q000187:drug effects; D005260:Female; D007267:Injections; D008297:Male; D010052:Ovariectomy; D010410:Penile Erection / Q000187:drug effects; D011301:Preoptic Area / Q000502:physiology*; D011725:Pyridines / Q000494:pharmacology; D051381:Rats; D017447:Receptors, Dopamine D1 / Q000187:drug effects*; D013268:Stimulation, Chemical
D001552:Benzazepines; D015259:Dopamine Agents; D011725:Pyridines; D017447:Receptors, Dopamine D1; D001058:Apomorphine