title: Antagonistic action of orphanin FQ on acupuncture analgesia in rat brain.
abstract: The influence of orphanin FQ (OFQ) (a newly discovered 17-amino acid peptide) on acupuncture analgesia (AA) was assessed in rat tail-flick model. Intracerebroventricular (i.c.v.) injection of OFQ (1 microgram) elicited a significant decrement of pain threshold which was abolished by the repeated pretreatment with antisense oligonucleotide (ASO) to OFQ receptor. Electroacupuncture (EA) induced an obvious analgesic effect; when OFQ was used combined with EA, it showed a dose-dependent effect on antagonizing the EA analgesia. When rat was repeatedly i.c.v. injected with ASO to block the synthesis of OFQ receptor, the EA analgesia was enhanced markedly. In this instance, the OFQ did not show antagonistic effect on EA analgesia any more. The results suggest that the OFQ play its antagonistic role on EA analgesia via activating OFQ receptor.
authors.affiliation: National Key Laboratory of Medical Neurobiology, Shanghai Medical University, China.
authors.forename: C B
authors.initials: CB
authors.lastname: Zhu
authors.forename: S F
authors.initials: SF
authors.lastname: Xu
authors.forename: X D
authors.initials: XD
authors.lastname: Cao
authors.forename: G C
authors.initials: GC
authors.lastname: Wu
authors.forename: X L
authors.initials: XL
authors.lastname: Zhang
authors.forename: M Y
authors.initials: MY
authors.lastname: Li
authors.forename: D F
authors.initials: DF
authors.lastname: Cui
authors.forename: C W
authors.initials: CW
authors.lastname: Chi
mesh_terms: D015670:Acupuncture Therapy; D000818:Animals; D001921:Brain / Q000187:drug effects*; D008297:Male; D018847:Opioid Peptides / Q000494:pharmacology*; D010146:Pain / Q000188:drug therapy*; D051381:Rats; D017207:Rats, Sprague-Dawley; D000097629:Nociceptin
chemical_list: D018847:Opioid Peptides; D000097629:Nociceptin