title: Plasma ACTH levels and beta-endorphin-like immunoreactivity following administration of luteinizing hormone-releasing hormone in Nelson's syndrome.
abstract: The effect of LH-RH (25 micrograms as a single i.v. bolus) on plasma corticotropin (ACTH) levels and beta-endorphin-like immunoreactivity was studied at 30 and 60 min in eight women with Nelson's syndrome. Plasma ACTH concentrations increased in three of them, while beta-endorphin-like immunoreactivity, measured in six cases, rose significantly at 30 min in all the patients under investigation. In the control group containing seven women with Nelson's syndrome, placebo (0.9% sodium chloride) administration did not induce any significant changes in ACTH concentrations or in beta-endorphin-like immunoreactivity. Our results suggest that a paradoxical stimulatory influence of LH-RH on pituitary Nelson's adenomas may play an important role in the adenoma hormonal activity and, perhaps, growth. Such an effect could be responsible for a rapid development of some pituitary neoplasms during pregnancy.
mesh_terms: D000236:Adenoma / Q000378:metabolism*; D000315:Adrenalectomy; D000324:Adrenocorticotropic Hormone / Q000097:blood / Q000378:metabolism*; D000328:Adult; D000818:Animals; D004723:Endorphins / Q000276:immunology / Q000378:metabolism*; D005260:Female; D007987:Gonadotropin-Releasing Hormone / Q000494:pharmacology*; D006801:Humans; D008875:Middle Aged; D009347:Nelson Syndrome / Q000378:metabolism*; D010911:Pituitary Neoplasms / Q000378:metabolism*; D010919:Placebos; D011817:Rabbits; D011863:Radioimmunoassay; D001615:beta-Endorphin
chemical_list: D004723:Endorphins; D010919:Placebos; D007987:Gonadotropin-Releasing Hormone; D001615:beta-Endorphin; D000324:Adrenocorticotropic Hormone