title: Involvement of the nitric oxide-cyclic GMP-protein kinase G-K+ channel pathway in the antihyperalgesic effects of bovine lactoferrin in a model of neuropathic pain.
abstract: The possible involvement of the nitric oxide (NO)-cyclic GMP (cGMP)-protein kinase G (PKG) pathway on bovine lactoferrin (BLF)-induced spinal antihyperalgesic activity was elucidated in sciatic nerve injured rats. Intrathecal BLF reduced thermal hyperalgesia in a dose-dependent manner. Pretreatment with NG-L-nitro-arginine methyl ester (L-NAME, non-specific inhibitor of NO synthase), 7-nitroindazole (7-NI, neuronal NO synthase inhibitor), 1H-[1,2,4]-oxadiazolo [4,3-a] quinoxalin-1-one (ODQ, guanylyl-cyclase inhibitor), (9S, 10R, 12R)-2,3,9,10,11,12-hexahydro-10-methoxy-2, 9-dimethyl-1-oxo-9, 12-epoxy-1H-diindolo-[1,2,3-fg:3',2',1'-kl]pyrrolo[3,4-i][1,6]benzodiazocine-10-carboxylic acid methyl ester (KT-5823, specific PKG inhibitor) or glybenclamide (ATP-sensitive K+ channel blocker), but not NG-D-nitro-arginine methyl ester (D-NAME, an inactive enantiomer of l-NAME), d-Phe-Cys-Tyr-d-Trp-Orn-Thr-NH2 (CTOP, selective mu-opioid receptor antagonist) or naloxone (nonselective opioid receptor antagonist) prevented BLF-induced antihyperalgesia. Data suggest that BLF-induced spinal antihyperalgesia could be due to activation of the NO-cGMP-PKG-K+ channel pathway and it is not mediated by mu-opioid receptor in a model of neuropathic pain.
authors.affiliation: Department of Anesthesiology, The First Affiliated Hospital, China Medical University, Shenyang 110001, PR China.
authors.forename: Jun
authors.initials: J
authors.lastname: Wang
authors.forename: Li-Cai
authors.initials: LC
authors.lastname: Zhang
authors.forename: You-Wen
authors.initials: YW
authors.lastname: Lv
authors.forename: Yong
authors.initials: Y
authors.lastname: Ji
authors.forename: Xue-Jun
authors.initials: XJ
authors.lastname: Yan
authors.forename: Jin-Pei
authors.initials: JP
authors.lastname: Xue
mesh_terms: D000700:Analgesics / Q000494:pharmacology / Q000627:therapeutic use; D000818:Animals; D002417:Cattle; D006152:Cyclic GMP / Q000378:metabolism; D017869:Cyclic GMP-Dependent Protein Kinases / Q000378:metabolism; D004195:Disease Models, Animal; D004305:Dose-Response Relationship, Drug; D004791:Enzyme Inhibitors / Q000494:pharmacology; D006930:Hyperalgesia / Q000188:drug therapy* / Q000378:metabolism / Q000503:physiopathology; D007278:Injections, Spinal; D007781:Lactoferrin / Q000494:pharmacology* / Q000627:therapeutic use; D008297:Male; D009292:Narcotic Antagonists / Q000494:pharmacology; D009475:Neurons, Afferent / Q000187:drug effects / Q000378:metabolism; D009569:Nitric Oxide / Q000378:metabolism; D010523:Peripheral Nervous System Diseases / Q000188:drug therapy* / Q000378:metabolism / Q000503:physiopathology; D026902:Potassium Channel Blockers / Q000494:pharmacology; D015221:Potassium Channels / Q000187:drug effects* / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D017450:Receptors, Opioid, mu / Q000187:drug effects / Q000378:metabolism; D015398:Signal Transduction / Q000187:drug effects* / Q000502:physiology
chemical_list: D000700:Analgesics; D004791:Enzyme Inhibitors; D009292:Narcotic Antagonists; D026902:Potassium Channel Blockers; D015221:Potassium Channels; D017450:Receptors, Opioid, mu; D009569:Nitric Oxide; D017869:Cyclic GMP-Dependent Protein Kinases; D007781:Lactoferrin; D006152:Cyclic GMP