title: Measurement of immunoreactive gamma-MSH in human plasma.
abstract: A radioimmunoassay for immunoreactive gamma-MSH (IR-gamma-MSH) in human plasma has been developed. The assay is capable of detecting normal basal circulating levels which range from less than 20-100 ng/1 at 0900 h. Plasma levels are raised concomitantly with ACTH during insulin induced hypoglycaemia and CRF stimulation and suppressed with dexamethasone. Chromatographic characterisation of IR-gamma-MSH in plasma demonstrates a major peak of IR-gamma-MSH, corresponding to purified glycosylated N-terminal pro-opiomelanocortin 1-76, when IR-gamma-MSH is secreted from the pituitary. In contrast IR-gamma-MSH produced ectopically appears to be heterogeneous.
mesh_terms: D000182:ACTH Syndrome, Ectopic / Q000097:blood / Q000188:drug therapy; D000307:Adrenal Gland Diseases / Q000097:blood / Q000188:drug therapy; D000324:Adrenocorticotropic Hormone / Q000097:blood; D001786:Blood Glucose / Q000378:metabolism; D002940:Circadian Rhythm; D003346:Corticotropin-Releasing Hormone / Q000494:pharmacology; D003907:Dexamethasone / Q000627:therapeutic use; D005260:Female; D006801:Humans; D007328:Insulin / Q000494:pharmacology; D008297:Male; D009074:Melanocyte-Stimulating Hormones / Q000097:blood*; D009347:Nelson Syndrome / Q000097:blood; D011863:Radioimmunoassay / Q000379:methods
chemical_list: D001786:Blood Glucose; D007328:Insulin; D003907:Dexamethasone; D000324:Adrenocorticotropic Hormone; D009074:Melanocyte-Stimulating Hormones; D003346:Corticotropin-Releasing Hormone