title: [Structure-function organization of ACTH: fragment ACTH 11-24--a functionally important site of the hormone molecule].
abstract: The steroidogenic and lipolytic activities of ACTH fragments (ACTH11-24--I, ACTH11-19--II, ACTH11-16--III and ACTH 17-24--IV) were studied. Fragments I--IV exert a steroidogenic effect in isolated fasciculata rat adrenal cells at concentrations of 1--500 micrograms/ml. The inner activity (alpha) and concentration at which a half-maximum effect is achieved (EC50) for fragments I and IV are 0.64+/-0.09 and 0.5--2.0 micrograms/ml, for fragment III--0.49+/-0.07 and 0.7 microgram/ml, respectively. Fragments I--IV have no effect on the lipolysis in isolated rat fat cells. The results obtained are indicative of the functional importance of fragment ACTH11-24 in manifestation of steroidogenic action of ACTH and suggest that the second active site of ACTH is enclosed within this amino acid sequence.
mesh_terms: D000273:Adipose Tissue / Q000187:drug effects / Q000378:metabolism*; D000311:Adrenal Glands / Q000187:drug effects / Q000378:metabolism*; D000324:Adrenocorticotropic Hormone / Q000494:pharmacology* / Q000502:physiology*; D000818:Animals; D001681:Biological Assay; D003366:Cosyntropin; D008066:Lipolysis / Q000187:drug effects; D010446:Peptide Fragments / Q000494:pharmacology*; D051381:Rats; D013256:Steroids / Q000096:biosynthesis; D013329:Structure-Activity Relationship
chemical_list: D010446:Peptide Fragments; D013256:Steroids; D003366:Cosyntropin; C034016:ACTH (11-24); D000324:Adrenocorticotropic Hormone
vernacular_title: Strukturno-funktsional'naia organizatsiia AKTG: fragment AKTG 11-24--funktsional'no vazhnyĭ uchastok molekuly gormona.