Evaluation of neopterin levels in an endotoxin induced experimental uveitis model in rabbit eyes

Neopterin is one of the markers emerging in the early stages of the cellular immunity.Uveitis is the inflammatory disease of the uveal tissue and one of the leading causes of thelegal blindness. In this study neopterin levels of intraocular fluids and serum were analyzedin the endotoxin-induced uveitis model.To produce endotoxin-induced anterior uveitis model, 0.05 ml E.Colilipopolysaccharide have been injected into the right eyes of 14 rabbits while left eyes havebeen evaluated as control group. From 7 rabbits in the first group aqueous fluid, vitreousand serum samples were drawn in the 24th hour while from the other 7 in the 2nd groupsamples were drawn in the 72th hour. Total protein and neopterin levels of these sampleswere measured by HPLS method. Simultaneously, eyes were bilaterally enucleated anduveitis induced histopathological changes were examined. Mean levels of neopterin inserum, aqueous fluid and vitreous were 4.02±1.6, 29.32±6.25, and 18.84±6.35 respectivelyin the 24th hour samples. In the 72th hour samples mean levels were 1.39±0.4 in serum,7.30±5.20 in aqueous fluid and 55.16±31.11 in vitreous and difference between two groupswere statistically significant (p=0.001). Total protein levels were also parallel withneopterin. Histopathologic evaluation revealed that in the first 24 hour inflammation issignificant in choroid and ciliary body and in 72 hour it is significant in retina.This study is important not only because it is the first study measuring neopterin inintraocular fluids and analizing neopterin levels in the experimental anterior uveitis modelbut also it is first study demonstrates neopterin level and activity correlation in the early andlate stages of inflammation.