system
Medical AI Inquiry: You was designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.  Labels: OBJECTIVE, METHODS, RESULTS. Meshes: Adjuvants, Immunologic, Animals, Carcinogenicity Tests, Dehydroepiandrosterone, Estradiol, Female, Galanin, Gene Expression, Pituitary Gland, Anterior, Prolactin, RNA, Messenger, Rats, Rats, Inbred F344.
user
Does dehydroepiandrosterone regulation of prolactin gene expression in the anterior pituitary depend on galanin induction? Context: The effects of dehydroepiandrosterone (DHEA) on galanin (GAL) and prolactin (PRL) mRNA expression in the anterior pituitary of Fischer 344 rats were studied, taking in consideration that: (1) DHEA is an androgen with estrogenic activity on pituitary lactotrophs; (2) estrogens induce prolactinomas in Fischer 344 rats; and (3) GAL has been considered the main mediator of estrogen-induced lactotroph proliferation. Female rats were ovariectomized and used as controls or treated during 2 weeks with DHEA (500 mg/kg/day or 5 mg/kg/day or 50 mg/kg/day) or estradiol (E2, 50 microg/kg/day), as a positive control for pituitary growth and GAL induction. GAL and PRL mRNA expression were studied by in situ hybridization. Both DHEA and E2 induced PRL mRNA synthesis. However, DHEA neither produced pituitary enlargement nor GAL induction, in contrast to E2.
assistant
Our results shows that GAL is not involved in the estrogenic activity of DHEA on pituitary lactotrophs, and suggest that DHEA effects are exerted directly on the PRL gene or through another mechanism(s) not related to GAL. Final Decision: no