title: In vitro effects of adenohypophysial hormones on rat pineal melatonin content and release.
abstract: The effect of adenohypophysial hormones on rat pineal melatonin content and release was examined in vitro. Medium concentration of radioimmunoassayable melatonin decreased after a 6 h exposure to 1-100 ng/ml FSH; pineal levels of melatonin were only decreased by 100 ng/ml FSH. LH (1-100 ng/ml) augmented significantly medium melatonin concentration, tissue levels being increased at 10 ng/ml LH. Parallel increases of explant and medium melatonin content were found after exposure to 1-100 ng/ml TSH. At the smallest concentration employed (1 ng/ml) prolactin increased melatonin content and release while at 100 ng/ml a significant depression of both parameters was found. Growth hormone (1-10 ng/ml) augmented melatonin levels in medium but failed to modify them at 100 ng/ml, although at this concentration tissue melatonin levels increased. ACTH did not modify pineal melatonin synthesis in vitro.
mesh_terms: D000324:Adrenocorticotropic Hormone / Q000494:pharmacology; D000818:Animals; D005640:Follicle Stimulating Hormone / Q000494:pharmacology; D013006:Growth Hormone / Q000494:pharmacology; D007986:Luteinizing Hormone / Q000494:pharmacology; D008297:Male; D008550:Melatonin / Q000378:metabolism*; D009924:Organ Culture Techniques; D010870:Pineal Gland / Q000187:drug effects / Q000378:metabolism*; D010908:Pituitary Hormones, Anterior / Q000494:pharmacology*; D011388:Prolactin / Q000494:pharmacology; D051381:Rats; D013972:Thyrotropin / Q000494:pharmacology
chemical_list: D010908:Pituitary Hormones, Anterior; D000324:Adrenocorticotropic Hormone; D011388:Prolactin; D007986:Luteinizing Hormone; D005640:Follicle Stimulating Hormone; D013972:Thyrotropin; D013006:Growth Hormone; D008550:Melatonin