Effects of morphine on the expression of cytokines and inflammatory mediators in a rabbit model of endotoxin-induced experimental uveitis

Author(s)

Ortencio, Kethye P. ^[1] ; Renzo, Roberta ^[1] ; Sobrinho, Alexandre A. F. B. ^[1] ; Kobashigawa, Karina Kamachi ^[1] ; Crivelaro, Roberta M. ^[1] ; Silva, Germana A. ^[1] ; Aldrovani, Marcela ^[1] ; Ribeiro, Alexandre Pinto ^[2] ; Mineo, Tiago W. P. ^[3] ; Laus, Jose Luiz ^[1]

Affiliation

^[1] Univ Estadual Paulista, Fac Ciencias Agr & Vet Jaboticabal, Dept Vet Clin Med & Surg, Ophthalmol Unit, Jaboticabal, SP - Brazil

^[2] UFMG, Fac Agron Med Vet & Zootecnia, Dept Vet Clin Med, Cuiaba, MT - Brazil

^[3] UFU, Inst Ciencias Biomed, Umuarama, MG - Brazil

• Document type: Journal article
• Source: Arquivos Brasileiros de Oftalmologia; v. 78, n. 6, p. 371-375, NOV-DEC 2015.
• Web of Science Citations: 1

Abstract

ABSTRACT Purpose: 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. (AU)

• FAPESP's process: 11/08734-8 - Effects of topical morphine over cytokines and inflammatory mediators in white New Zeland rabbits with induced uveitis
• Grantee: José Luiz Laus
• Support Opportunities: Regular Research Grants