title: Isolation from bovine brain of a novel analgesic pentapeptide, neo-kyotorphin, containing the Tyr-Arg (kyotorphin) unit.
abstract: A novel analgesic peptide, isolated from the bovine brain, was found to contain the Tyr-Arg (kyotorphin) unit at the C-terminal portion. This peptide, in the methanol-soluble fraction, was isolated by gel filtration and cation exchange chromatography. This peptide was termed "neo-kyotorphin" and the amino acid sequence is Thr-Ser-Lys-Tyr-Arg. The synthetically prepared neo-kyotorphin proved to have a dose-dependent analgesic effect in mice. The median analgesic dose, ED50 of neo-kyotorphin was 195 nmol/mouse (intracisternal injection), with the tail pinch test, and the potency was approximately equal that of Leu-enkephalin.
mesh_terms: D000596:Amino Acids / Q000032:analysis; D000700:Analgesics; D000818:Animals; D001923:Brain Chemistry; D002417:Cattle; D055598:Chemical Phenomena; D002621:Chemistry; D002851:Chromatography, High Pressure Liquid / Q000379:methods; D002855:Chromatography, Thin Layer; D004590:Electrophoresis, Paper; D004723:Endorphins / Q000032:analysis* / Q000302:isolation & purification* / Q000494:pharmacology; D006168:Guinea Pigs; D006632:Histamine / Q000032:analysis; D007082:Ileum / Q000187:drug effects; D066298:In Vitro Techniques; D051379:Mice; D009119:Muscle Contraction / Q000187:drug effects; D009130:Muscle, Smooth / Q000187:drug effects
chemical_list: D000596:Amino Acids; D000700:Analgesics; D004723:Endorphins; C019448:kyotorphin; D006632:Histamine; C036450:neo-kyotorphin