title: A brain octadecaneuropeptide generated by tryptic digestion of DBI (diazepam binding inhibitor) functions as a proconflict ligand of benzodiazepine recognition sites.
abstract: An octadecaneuropeptide (ODN) produced by the tryptic digestion of DBI was purified and sequenced and its activity on the Vogel test determined. In vitro ODN displaces 3H-diazepam from specific brain recognition sites and injected intraventricularly in thirsty rats facilitates the onset of behavioral inhibition elicited by punishment. The alpha-amide derivative of ODN is devoid of either action. Evidence is presented suggesting that DBI sequence includes at least two replicas of ODN or one replica of ODN and a fragment with similar if not identical amino acid sequence but identical biological activity.
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001522:Behavior, Animal / Q000187:drug effects*; D002851:Chromatography, High Pressure Liquid; D003220:Conflict, Psychological / Q000187:drug effects*; D003488:Cyanogen Bromide; D026261:Diazepam Binding Inhibitor; D006868:Hydrolysis; D009419:Nerve Tissue Proteins / Q000032:analysis / Q000494:pharmacology*; D010446:Peptide Fragments / Q000032:analysis / Q000494:pharmacology*; D051381:Rats; D011963:Receptors, GABA-A / Q000378:metabolism*; D014357:Trypsin
chemical_list: D026261:Diazepam Binding Inhibitor; D009419:Nerve Tissue Proteins; D010446:Peptide Fragments; D011963:Receptors, GABA-A; D014357:Trypsin; D003488:Cyanogen Bromide