Effects of metachlopromide-induced hyperprolactinemia on serum testosterone and its response to hCG in adult male common marmosets (Callithrix jacchus)

Intramuscular administration of metachlopromide (2.5, 10, and 25 mg) induced increase in serum prolactin levels. Following 10 and 25 mg dose levels, prolactin levels were elevated at least for 8 hr. Single administration of metachlopromide failed to affect the nocturnal rise in circulating levels of testosterone. Daily treatment of metachlopromide (10 mg) for 30 days suppressed the nocturnal elevation of testosterone on day 28 of treatment. However, the hCG-stimulated testosterone production on day 30 was unaffected. The results of the present study demonstrate that metachlopromide-induced hyperprolactinemia in adult male common marmosets affects the hypothalamo-pituitary axis without any effect on testicular response to hCG.