title: Contribution of nociceptin/orphanin FQ receptors to the anti-nociceptive and hypothermic effects of dipyrone.
abstract: BACKGROUND
  Dipyrone is one of the most commonly used non-opioid analgesic and antipyretic drug. Its anti-nociceptive and hypothermic effects have long been suspected to be centrally mediated. The involvement of the most recently discovered opioid peptide, nociceptin/orphanin FQ (N/OFQ), and its receptor (NOP) in pain transmission is controversial. It appears to be pro-nociceptive when administered supra-spinally, but exerts anti-nociceptive effects when injected spinally or systemically.
  
  
  OBJECTIVE
  Investigation of the role of the N/OFQ system in paracetamol-induced anti-nociception and hypothermia led us to determine its role in the anti-nociceptive and hypothermic effects of dipyrone. Material and Methods Hot-plate and tail-flick tests were used to assess nociception, and a rectal thermometer was used to measure rectal temperature in mice.
  
  
  RESULTS
  Mice injected with dipyrone (150, 300, 600 mg/kg, i.p.) displayed dose-related anti-nociception and hypothermia. The NOP receptor antagonist JTC-801 (3 mg/kg, i.p.), at a dose that exerted no effect when used alone, alleviated dipyrone-induced anti-nociception but did not reverse dipyrone-induced hypothermia.
  
  
  CONCLUSIONS
  We conclude that NOP receptors participate in the anti-nociceptive, but not in the hypothermic, effects of dipyrone.
authors.affiliation: Department of Medical Pharmacology, Faculty of Medicine,Trakya University,Edirne,Turkey.
authors.forename: Ismet Hande
authors.initials: IH
authors.lastname: Ertin
authors.affiliation: Department of Medical Pharmacology, Faculty of Medicine,Trakya University,Edirne,Turkey.
authors.forename: Ozgur
authors.initials: O
authors.lastname: Gunduz
authors.affiliation: Department of Medical Pharmacology, Faculty of Medicine,Trakya University,Edirne,Turkey.
authors.forename: Ahmet
authors.initials: A
authors.lastname: Ulugol
mesh_terms: D000634:Aminoquinolines / Q000494:pharmacology; D000818:Animals; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000037:antagonists & inhibitors / Q000494:pharmacology; D001549:Benzamides / Q000494:pharmacology; D004177:Dipyrone / Q000037:antagonists & inhibitors / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D007035:Hypothermia / Q000139:chemically induced* / Q000503:physiopathology; D008297:Male; D051379:Mice; D059225:Nociception / Q000187:drug effects* / Q000502:physiology*; D010147:Pain Measurement / Q000187:drug effects; D011957:Receptors, Opioid / Q000187:drug effects / Q000502:physiology*; D000094942:Nociceptin Receptor
chemical_list: D000634:Aminoquinolines; D000894:Anti-Inflammatory Agents, Non-Steroidal; D001549:Benzamides; C433236:N-(4-amino-2-methylquinolin-6-yl)-2-(4-ethylphenoxymethyl)benzamide; D011957:Receptors, Opioid; D004177:Dipyrone; D000094942:Nociceptin Receptor; C000722287:Oprl1 protein, mouse
keywords: N/OFQ