title: Effects of morphine on the expression of cytokines and inflammatory mediators in a rabbit model of endotoxin-induced experimental uveitis.
abstract: OBJECTIVE
  To evaluate the effects of 1% morphine instillation on clinical parameters, aqueous humor turbidity, and expression levels of tumor necrosis factor alpha (TNF-α), interleukin-1 beta (IL-1beta), prostaglandin E2 (PGE2), and myeloperoxidase (MPO) in rabbits with endotoxin-induced experimental uveitis.
  
  
  METHODS
  Twenty four New Zealand white rabbits were divided into four groups (n=6 each): control (CG), morphine (MG), naloxone (NG), and morphine-naloxone (MNG) groups. Under dissociative anesthesia, 0.1 mL of solution containing 0.2 µg of lipopolysaccharide (LPS) endotoxin from the Salmonella typhimurium cell wall was injected in the vitreous chamber. Clinical evaluations (conjunctical hyperemia, chemosis blepharospasm, and ocular discharge) and laser flaremetry were performed before (baseline), and 10 and 20 hours after induction of uveitis. Rabbits were subsequently euthanized and eyes were enucleated to quantify expression levels of TNF-α, IL-1 beta, PGE2, and MPO.
  
  
  RESULTS
  No significant differences in clinical parameters and flare values were observed between the study groups. TNF-α and IL-1 beta levels increased significantly in the CG, MG, NG, and MNG groups compared to baseline (P<0.05). Significant differences in PGE2 levels were observed between the MG and NMG groups (P<0.05). A trend toward increased MPO activity was observed in response to uveitis induction; however, this trend did not reach statistical significance (P>0.05).
  
  
  CONCLUSIONS
  Morphine has no effect on clinical parameters, flare, or expression levels of inflammatory mediators in a rabbit model of uveitis induced by intravitreal injection of LPS.
authors.affiliation: Ophthalmology Unit, Department of Veterinary Clinical Medicine and Surgery, Faculdade de Ciências Agrárias e Veterinárias de Jaboticabal, Universidade Estadual Paulista "Julio de Mesquita Filho", Jaboticabal, SP, Brazil.
authors.forename: Kethye P
authors.initials: KP
authors.lastname: Ortencio
authors.affiliation: Ophthalmology Unit, Department of Veterinary Clinical Medicine and Surgery, Faculdade de Ciências Agrárias e Veterinárias de Jaboticabal, Universidade Estadual Paulista "Julio de Mesquita Filho", Jaboticabal, SP, Brazil.
authors.forename: Roberta
authors.initials: R
authors.lastname: Renzo
authors.affiliation: Ophthalmology Unit, Department of Veterinary Clinical Medicine and Surgery, Faculdade de Ciências Agrárias e Veterinárias de Jaboticabal, Universidade Estadual Paulista "Julio de Mesquita Filho", Jaboticabal, SP, Brazil.
authors.forename: Alexandre A F
authors.initials: AA
authors.lastname: Sobrinho B
authors.affiliation: Ophthalmology Unit, Department of Veterinary Clinical Medicine and Surgery, Faculdade de Ciências Agrárias e Veterinárias de Jaboticabal, Universidade Estadual Paulista "Julio de Mesquita Filho", Jaboticabal, SP, Brazil.
authors.forename: Karina Kamachi
authors.initials: KK
authors.lastname: Kobashigawa
authors.affiliation: Ophthalmology Unit, Department of Veterinary Clinical Medicine and Surgery, Faculdade de Ciências Agrárias e Veterinárias de Jaboticabal, Universidade Estadual Paulista "Julio de Mesquita Filho", Jaboticabal, SP, Brazil.
authors.forename: Roberta M
authors.initials: RM
authors.lastname: Crivelaro
authors.affiliation: Ophthalmology Unit, Department of Veterinary Clinical Medicine and Surgery, Faculdade de Ciências Agrárias e Veterinárias de Jaboticabal, Universidade Estadual Paulista "Julio de Mesquita Filho", Jaboticabal, SP, Brazil.
authors.forename: Germana A
authors.initials: GA
authors.lastname: Silva
authors.affiliation: Ophthalmology Unit, Department of Veterinary Clinical Medicine and Surgery, Faculdade de Ciências Agrárias e Veterinárias de Jaboticabal, Universidade Estadual Paulista "Julio de Mesquita Filho", Jaboticabal, SP, Brazil.
authors.forename: Marcela
authors.initials: M
authors.lastname: Aldrovani
authors.affiliation: Departament of Veterinary Clinical Medicine, Faculdade de Agronomia, Medicina Veterinária e Zootecnia, Universidade Federal de Mato Grosso, Cuiabá, MT, Brazil.
authors.forename: Alexandre Pinto
authors.initials: AP
authors.lastname: Ribeiro
authors.affiliation: Instituto de Ciências Biomédicas, Universidade Federal de Uberlândia, Umuarama, MG, Brazil.
authors.forename: Tiago W P
authors.initials: TW
authors.lastname: Mineo
authors.affiliation: Ophthalmology Unit, Department of Veterinary Clinical Medicine and Surgery, Faculdade de Ciências Agrárias e Veterinárias de Jaboticabal, Universidade Estadual Paulista "Julio de Mesquita Filho", Jaboticabal, SP, Brazil.
authors.forename: José Luiz
authors.initials: JL
authors.lastname: Laus
mesh_terms: D000701:Analgesics, Opioid / Q000494:pharmacology* / Q000627:therapeutic use; D000818:Animals; D001082:Aqueous Humor / Q000187:drug effects; D015232:Dinoprostone / Q000032:analysis*; D004195:Disease Models, Animal; D004731:Endotoxins; D007322:Instillation, Drug; D053583:Interleukin-1beta / Q000032:analysis*; D009020:Morphine / Q000494:pharmacology* / Q000627:therapeutic use; D009195:Peroxidase / Q000032:analysis*; D011817:Rabbits; D012016:Reference Values; D015203:Reproducibility of Results; D013997:Time Factors; D014409:Tumor Necrosis Factor-alpha / Q000032:analysis*; D014602:Uvea / Q000187:drug effects / Q000473:pathology; D014605:Uveitis / Q000188:drug therapy* / Q000209:etiology / Q000473:pathology
chemical_list: D000701:Analgesics, Opioid; D004731:Endotoxins; D053583:Interleukin-1beta; D014409:Tumor Necrosis Factor-alpha; D009020:Morphine; D009195:Peroxidase; D015232:Dinoprostone