title: Involvement of cannabinoid CB1 receptors in the antinociceptive effect of dipyrone.
abstract: Cannabinoid CB1 receptors have been implicated in the antinociceptive effect of paracetamol. In the current study, we examined whether blockade of CB1 receptors prevent the analgesic activity of dipyrone, in a similar way to paracetamol. Hot-plate and tail-flick tests were used to assess the antinociceptive activity in mice. Dipyrone and WIN 55,212-2, a cannabinoid agonist, exerted significant antinociceptive effects in both hot-plate and tail flick tests. The CB1 receptor antagonist, AM-251 (3 mg/kg), at a dose which had no effect when used alone, did not alter the antinociceptive effect of dipyrone, whereas completely prevented the antinociceptive activity of WIN 55,212-2 in both thermal antinociceptive tests. Our findings suggest that, unlike paracetamol, cannabinoid CB1 receptors do not participate in the antinociceptive action of dipyrone when acute pain tests used.
authors.affiliation: Department of Medical Pharmacology, Faculty of Medicine, Trakya University, 22030, Edirne, Turkey.
authors.forename: Pinar
authors.initials: P
authors.lastname: Elmas
authors.forename: Ahmet
authors.initials: A
authors.lastname: Ulugol
mesh_terms: D000700:Analgesics / Q000494:pharmacology / Q000627:therapeutic use*; D000818:Animals; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000494:pharmacology / Q000627:therapeutic use*; D048588:Benzoxazines / Q000494:pharmacology / Q000627:therapeutic use; D063386:Cannabinoid Receptor Agonists / Q000494:pharmacology / Q000627:therapeutic use*; D063387:Cannabinoid Receptor Antagonists / Q000494:pharmacology; D004177:Dipyrone / Q000494:pharmacology / Q000627:therapeutic use*; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D009025:Morpholines / Q000494:pharmacology / Q000627:therapeutic use; D009281:Naphthalenes / Q000494:pharmacology / Q000627:therapeutic use; D010146:Pain / Q000188:drug therapy*; D010147:Pain Measurement; D017288:Pain Threshold / Q000187:drug effects*; D010880:Piperidines / Q000494:pharmacology; D011720:Pyrazoles / Q000494:pharmacology; D043884:Receptor, Cannabinoid, CB1 / Q000819:agonists*
chemical_list: D000700:Analgesics; D000894:Anti-Inflammatory Agents, Non-Steroidal; D048588:Benzoxazines; D063386:Cannabinoid Receptor Agonists; D063387:Cannabinoid Receptor Antagonists; D009025:Morpholines; D009281:Naphthalenes; D010880:Piperidines; D011720:Pyrazoles; D043884:Receptor, Cannabinoid, CB1; C103505:AM 251; C070417:(3R)-((2,3-dihydro-5-methyl-3-((4-morpholinyl)methyl)pyrrolo-(1,2,3-de)-1,4-benzoxazin-6-yl)(1-naphthalenyl))methanone; D004177:Dipyrone