title: Somatostatin-20: a novel NH2-terminally extended form of somatostatin isolated from porcine duodenum together with somatostatin-28 and somatostatin-25.
abstract: Liquid chromatography of porcine duodenal extracts, in conjugation with bioassay on guinea-pig ileum myenteric plexus longitudinal muscle preparation, yielded substances which inhibited electrically-evoked twitches of the preparations, but whose actions could not be reversed by naloxone, an opioid antagonist. The substances were determined to be NH2-terminally extended forms of somatostatin, i.e. somatostatin-28, somatostatin-25 and somatostatin-20. This is the first time that somatostatin-20 has been isolated from animal tissues.
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001681:Biological Assay; D002851:Chromatography, High Pressure Liquid; D004386:Duodenum / Q000378:metabolism*; D006168:Guinea Pigs; D006801:Humans; D007082:Ileum / Q000187:drug effects; D009130:Muscle, Smooth / Q000187:drug effects; D051381:Rats; D013004:Somatostatin / Q000031:analogs & derivatives* / Q000302:isolation & purification* / Q000494:pharmacology; D053561:Somatostatin-28; D013552:Swine
chemical_list: D013004:Somatostatin; C026568:somatostatin 25; D053561:Somatostatin-28; C043961:somatostatin 20