MedicineEndocrinologyPharmacologyNeuroendocrinologyNeuropharmacologyPsychopharmacologyHormonal InfluencesHypothalamic-pituitary RegulationHypothalamic-pituitary-gonadal AxisReproductive NeuroendocrinologyReproductive PharmacologyDopamine D2-like ReceptorsDopamine-mediated InhibitionHypothalamic Regulation Of ProlactinHypothalamic-pituitary-prolactin AxisMale Prolactin PhysiologyMale Sexual BehaviorProlactin PharmacologyProlactin Secretion Regulation
Acute intraperitoneal administration of bromopride (BRO), a dopamine D2 blocker used as an anti-emetic drug in gastroenterology was tested in male and female rats for its effect on prolactin (PRL) serum levels and on sexual behavior. Rats that received 2.5 mg/kg BRO, the lowest dose tested, showed a maximal increase in PRL serum levels. Male rats that received 5.0 mg/kg BRO showed higher postejaculatory mount latency and postejaculatory intromission latency than controls. Rats treated with 10.0 mg/kg BRO showed higher mount latency, intromission latency, ejaculation latency, postejaculatory mount latency and a lower percentage of animals showing mount and ejaculation. Female rats that received 5.0 mg/kg BRO showed a lower lordosis quotient. The data suggest that blockade of postsynaptic dopamine D2 receptors inhibits male and female sexual behavior and that this inhibition is not related solely to the increase in PRL levels.