title: Adrenocorticotropin- and opiate-like hormones from pituitaries of the sockeye salmon Oncorhynchus nerka.
abstract: The pituitaries of vitellogenic sockeye salmon (Oncorhynchus nerka) were extracted with a mixture of acetone, water, and hydrochloric acid. The precipitate which formed upon the addition of a copious volume of acetone to the extract, designated acid acetone powder, was subjected to salt fractionation and desalting, followed by ion-exchange chromatography on CM-cellulose. An unadsorbed fraction (S-1) and four adsorbed fractions (S-2, S-3, S-4 and S-5) were obtained. Adrenocorticotropic activity was detected in the fractions by their ability to stimulate isolated rat adrenal decapsular cells to produce corticosterone and by their immunoreactivities in an adrenocorticotropin-specific radioimmunoassay. The steroidogenic activities of all fractions, except S-4, were blocked by corticotropin inhibiting peptide. Opiate activity was detected in the fractions by their ability to inhibit the binding of either [3H]naloxone or (D-ala2, D-leu5)-[3H]enkephalin to rat brain membranes. There was a discrepancy in the potencies of the five fractions in the two opiate radioreceptor assays, indicating the presence of opiate peptides with different affinities of binding to the micron- and delta-opiate receptors of the rat brain. There was a separation between adrenocorticotropic and opiate receptor binding activities, suggesting that the activities were due to separate molecular entities.
mesh_terms: D000302:Adrenal Cortex / Q000187:drug effects / Q000378:metabolism; D000324:Adrenocorticotropic Hormone / Q000302:isolation & purification* / Q000494:pharmacology; D000818:Animals; D001921:Brain / Q000378:metabolism; D002462:Cell Membrane / Q000378:metabolism; D003345:Corticosterone / Q000096:biosynthesis; D004745:Enkephalins / Q000302:isolation & purification* / Q000494:pharmacology; D007700:Kinetics; D008297:Male; D010902:Pituitary Gland / Q000032:analysis*; D051381:Rats; D011919:Rats, Inbred Strains; D011957:Receptors, Opioid / Q000187:drug effects / Q000378:metabolism; D012474:Salmon
chemical_list: D004745:Enkephalins; D011957:Receptors, Opioid; D000324:Adrenocorticotropic Hormone; D003345:Corticosterone