title: Effects of large doses of estrogen on prolactin and growth hormone release.
abstract: The effects of large doses of estrogen on prolactin (PRL) release were assessed. Circulating PRL levels in response to intravenous infusion of 17 beta-estradiol (E2), at a rate of 50 mug per hour for 4 hours, were studied in 10 subjects, and a chronic administration of ethinyl estradiol (EE) at a dose of 400 mug per day, for 1 week, was evaluated in five hypogonadal subjects. There was a significant depression of serum level of PRL during the E2 infusion and a significant increase in PRL release after discontinuation of the infusion. The chronic treatment of large doses of EE induced a more rapid (within 36 hours) and a significantly greater elevation of PRL levels at the end of 1 week treatment than those found during smaller doses of EE administration, as reported previously. These data suggest that acute treatment of estrogen may have a biphasic action on the pituitary PRL section and that the augmentatory effect of estrogen on PRL secretion is dose-dependent in human beings.
mesh_terms: D000328:Adult; D004305:Dose-Response Relationship, Drug; D004958:Estradiol / Q000008:administration & dosage / Q000494:pharmacology; D004967:Estrogens / Q000008:administration & dosage* / Q000494:pharmacology; D004997:Ethinyl Estradiol / Q000008:administration & dosage / Q000494:pharmacology; D005260:Female; D013006:Growth Hormone / Q000378:metabolism*; D006801:Humans; D008875:Middle Aged; D011388:Prolactin / Q000378:metabolism*
chemical_list: D004967:Estrogens; D004997:Ethinyl Estradiol; D004958:Estradiol; D011388:Prolactin; D013006:Growth Hormone