title: Possible involvement of endogenous nociceptin/orphanin FQ in the pain-related behavioral responses induced by its own metabolite, nociceptin/orphanin FQ(14-17).
abstract: Nociceptin/orphanin FQ(14-17) (N/OFQ(14-17)) is one of the major fragments that are released from N/OFQ, an endogenous ligand for the opioid receptor like-1 (ORL-1) receptor by endopeptidase 24.11. In the present study, we determined the pharmacological profiles of N/OFQ(14-17) on pain-related behavioral responses in the mouse. Intrathecal (i.t.) administration of N/OFQ(14-17) (5-160 pmol) evoked pain-related behaviors, and these behavioral responses were reduced by i.t. co-administration of an ORL-1 receptor antagonist, [Nphe(1)]N/OFQ(1-13)NH2 (4 pmol). However, in the ligand-binding receptor assay, N/OFQ(14-17) had no affinity for the ORL-1 receptor. Furthermore, i.t. pretreatment with an antiserum against N/OFQ (1:50) diminished the N/OFQ(14-17)-induced pain-related behaviors, suggesting that endogenous N/OFQ is involved in their expression. Therefore, N/OFQ(14-17)-induced pain-related behaviors may be mediated through the release of endogenous N/OFQ in the mouse spinal cord.
authors.affiliation: Department of Physiology and Anatomy, Tohoku Pharmaceutical University, 4-4-1 Komatsushima, Aoba-ku, Sendai 981-8558, Japan.
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Watanabe
authors.forename: Hirokazu
authors.initials: H
authors.lastname: Mizoguchi
authors.forename: Tohru
authors.initials: T
authors.lastname: Orito
authors.forename: Sou
authors.initials: S
authors.lastname: Katsuyama
authors.forename: Akihiko
authors.initials: A
authors.lastname: Yonezawa
authors.forename: Chizuko
authors.initials: C
authors.lastname: Watanabe
authors.forename: Tsukasa
authors.initials: T
authors.lastname: Sakurada
authors.forename: Shinobu
authors.initials: S
authors.lastname: Sakurada
mesh_terms: D000818:Animals; D001483:Base Sequence; D001522:Behavior, Animal / Q000187:drug effects / Q000502:physiology; D006634:Histamine H1 Antagonists / Q000494:pharmacology; D008297:Male; D051379:Mice; D008845:Microinjections; D020319:Oligodeoxyribonucleotides, Antisense / Q000235:genetics / Q000494:pharmacology; D018847:Opioid Peptides / Q000037:antagonists & inhibitors / Q000235:genetics / Q000494:pharmacology / Q000502:physiology*; D010146:Pain / Q000503:physiopathology* / Q000523:psychology; D010446:Peptide Fragments / Q000008:administration & dosage / Q000494:pharmacology*; D000097629:Nociceptin
chemical_list: D006634:Histamine H1 Antagonists; D020319:Oligodeoxyribonucleotides, Antisense; D018847:Opioid Peptides; D010446:Peptide Fragments; D000097629:Nociceptin