title: Involvement of interleukin-1beta in systemic morphine effects on paw oedema in a mouse model of acute inflammation.
abstract: Recent studies suggest that peripheral morphine may represent a valuable treatment in acute inflammatory painful diseases through peripheral or central mechanisms. In the present study, anti-inflammatory effects of systemic morphine on carrageenan-induced hind paw oedema were examined in a model of peripheral acute oedema in mice. Carrageenan induced a time-dependent inflammation that was maximal 3 h after administration. While intraperitoneal administration of morphine sulfate at a low dose (1 mg/kg) increased carrageenan-induced hind paw oedema, intraperitoneal injection of morphine sulfate at a high dose (7 mg/kg) resulted in significant anti-inflammatory effects on carrageenan-induced hind paw oedema. These anti-inflammatory effects were blocked by pretreatment with naloxone. Measuring the serum levels of interleukin-1beta revealed that increases in serum levels of this cytokine were involved in morphine anti-inflammatory effects. Pretreatment with naloxone decreased interleukin-1beta serum levels near to those of control group. In conclusion, these data demonstrate that morphine produced pro- or anti-inflammatory effects in a dose-dependent manner through peripheral or central mechanisms. The observed anti-inflammatory effects may be due to an increase in the cytokine production and/or release by host immune systems.
authors.affiliation: Department of Immunology and Allergy, Medical Center for Children, Tehran University of Medical Science, Tehran, Iran.
authors.forename: Z
authors.initials: Z
authors.lastname: Pourpak
authors.forename: A
authors.initials: A
authors.lastname: Ahmadiani
authors.forename: M
authors.initials: M
authors.lastname: Alebouyeh
mesh_terms: D000701:Analgesics, Opioid / Q000037:antagonists & inhibitors / Q000494:pharmacology*; D000818:Animals; D000893:Anti-Inflammatory Agents / Q000037:antagonists & inhibitors / Q000494:pharmacology*; D002351:Carrageenan; D004195:Disease Models, Animal; D004487:Edema / Q000188:drug therapy* / Q000276:immunology; D006614:Hindlimb; D007249:Inflammation / Q000188:drug therapy / Q000276:immunology; D007375:Interleukin-1 / Q000037:antagonists & inhibitors / Q000097:blood / Q000276:immunology*; D008297:Male; D051379:Mice; D009020:Morphine / Q000037:antagonists & inhibitors / Q000494:pharmacology*; D009270:Naloxone / Q000494:pharmacology*; D009292:Narcotic Antagonists / Q000494:pharmacology
chemical_list: D000701:Analgesics, Opioid; D000893:Anti-Inflammatory Agents; D007375:Interleukin-1; D009292:Narcotic Antagonists; D009270:Naloxone; D009020:Morphine; D002351:Carrageenan