title: Effects of various neuropeptides on the secretion of proopiomelanocortin-derived peptides by a cultured pituitary adenoma causing Nelson's syndrome.
abstract: To clarify whether various neuropeptides found in the hypothalamus act directly on a pituitary adenoma causing Nelson's syndrome, we examined the influence of these peptides on the secretion of immunoreactive ACTH, beta-endorphin, and melanotropins, the proopiomelanocortin (POMC)-derived peptides, by the cultured pituitary adenoma from a patient with Nelson's syndrome. Results showed that somatostatin-14 and somatostatin-28 suppressed the secretion of POMC-derived peptides by the adenoma and that somatostatin-28 was as potent as somatostatin-14. Other neuropeptides such as arginine vasopressin, vasoactive intestinal polypeptide, and oxytocin stimulate the secretion of POMC-derived peptides. Substance P, TRF, Met-enkephalin and Leu-enkephalin were also found to modulate the secretion of POMC-derived peptides. This suggests that the adenoma may have multiple receptors to various neuropeptides.
mesh_terms: D000236:Adenoma / Q000378:metabolism*; D000324:Adrenocorticotropic Hormone / Q000378:metabolism; D001127:Arginine Vasopressin / Q000494:pharmacology; D046508:Culture Techniques; D004723:Endorphins / Q000378:metabolism*; D006801:Humans; D009074:Melanocyte-Stimulating Hormones / Q000378:metabolism; D009347:Nelson Syndrome / Q000378:metabolism*; D010455:Peptides / Q000494:pharmacology*; D010911:Pituitary Neoplasms / Q000378:metabolism*; D013004:Somatostatin / Q000494:pharmacology; D001615:beta-Endorphin; D008083:beta-Lipotropin / Q000378:metabolism
chemical_list: D004723:Endorphins; D010455:Peptides; D001127:Arginine Vasopressin; D013004:Somatostatin; D001615:beta-Endorphin; D000324:Adrenocorticotropic Hormone; D009074:Melanocyte-Stimulating Hormones; D008083:beta-Lipotropin