Luteinizing hormone response to domperidone in hyperprolactinaemic women with pituitary microadenomas

Administration of a dopamine (DA) antagonist, domperidone, increased circulating levels of LH in hyperprolactinaemic-amenorrhoeic women with pituitary microadenomas but not in normal women in the early follicular phase of the menstrual cycle. This drug does not readily cross the blood-brain barrier and therefore the site of action of domperidone could be the pituitary gland or the median eminence. As the simultaneous administration of GnRH and domperidone did not increase the GnRH-induced LH release in hyperprolactinaemic women, the site of action of domperidone is likely to be the median eminence.