Inhibitory effect of the dopamine agonist bromocriptine on the postcastration gonadotrophin rise in women.

Basal or stimulated gonadotrophin plasma levels were measured after bilateral ovariectomy in untreated and bromocriptine (BCT)-treated normal women. BCT was orally administered from the 7th to the 14th day after ovariectomy at a dose of 3.75 mg/day. BCT significantly (P less than 0.05) inhibited LH release, both basally and after LRF stimulation. Plasma FSH levels were also reduced in treated subjects, but this decrease did not reach statistical significance relative to controls. The blunted postcastration gonadotrophin rise found with BCT administration suggests that pituitary gonadotropin secretion is, in part, under dopaminergic inhibitory control.