Oxytocin inhibits male sexual behavior in prairie voles.

Intracerebroventricular (ICV) injection of oxytocin (300 ng) produced an immediate cessation in sexual behavior in sexually active male prairie voles (Microtus ochrogaster). Other social behaviors including social contact, aggression, and autogrooming were not significantly affected by oxytocin, but males that received oxytocin ICV, versus injections that missed the ventricles, showed more sleep postures. Sexual behavior remained inhibited for at least 24 hours and was not activated in tests with a novel receptive female. Sexual and social behavior were not significantly altered in animals in which the oxytocin injection missed the ventricles or in saline-treated males. These findings are consistent with the hypothesis that oxytocin plays a role in sexual satiety.