title: Inhibitory effect of adrenocorticotropin on corticotropin- releasing factor release from rat hypothalamus in vitro.
abstract: Effects of ACTH and ACTH fragments on immunoreactive corticotropin-releasing factor (I-CRF) release were examined by utilizing rat hypothalamic perifusion system and a rat CRF RIA. ACTH-(1-39) had a dose-related inhibitory effect on I-CRF release. Mean percent inhibition of I-CRF release was 52, 55, 49, 30 and less than 5 percent by ACTH-(1-39), ACTH-(1-24), alpha-MSH and ACTH-(18-39) at 2.2 nM concentrations, respectively. These results suggest the presence of a negative short-loop feedback mechanism, and also that the active core is contained within the ACTH-(1-17) structure.
mesh_terms: D000324:Adrenocorticotropic Hormone / Q000494:pharmacology*; D000818:Animals; D053497:Corticotropin-Like Intermediate Lobe Peptide; D003346:Corticotropin-Releasing Hormone / Q000378:metabolism*; D003366:Cosyntropin / Q000494:pharmacology; D007031:Hypothalamus / Q000187:drug effects / Q000378:metabolism*; D066298:In Vitro Techniques; D007700:Kinetics; D008297:Male; D009074:Melanocyte-Stimulating Hormones / Q000494:pharmacology; D010446:Peptide Fragments / Q000494:pharmacology; D051381:Rats
chemical_list: D010446:Peptide Fragments; D003366:Cosyntropin; D053497:Corticotropin-Like Intermediate Lobe Peptide; D000324:Adrenocorticotropic Hormone; D009074:Melanocyte-Stimulating Hormones; D003346:Corticotropin-Releasing Hormone; C028238:ACTH (1-17)