RESUMO
Background Lewis rat is a commonly used specie in experimental autoimmune uveitis(EAU).However,the characteristics of EAU,especially ocular uhrastructural change,are rarely reported.Objective This study was to investigate the inflammatory characteristics and ocular uhrastructure of EAU models in Lewis rat.Methods EAU models were induced in 12 SPF female Lewis rats(6-8 weeks old)by injection of complete Freund adjuvant(CFA) containing interphotoreceptor retinoid-binding protein (IRBP,1177-1191) and tuberculin (TB) into footpads,napes and back of the body,and 6 normal matched rats were used as normal controls.The diet and drinking,temperature and behavior acts of the rats were recorded during the observational duration.Ocular manifestations were examined under the slit lamp biomicroscope after modeling and scored.Eyeballs were obtained in 12 days after modeling for histopathological examination,and the ultrastructures of eyeballs were observed under the scanning electron microscope and transmission electron microscope.The use and care of the animals complied with Statement of ARVO.Results The food-intake was (190.00± 18.03)g in the model group,and that in the control group was (285.33 ±28.02) g,showing a significant difference between them (t =4.955,P =0.012).The drinking-water volume of rats was (241.67±t 18.56)ml in the model group,which was significantly less than (289.67± 18.18)ml in the control group,showing a significant difference between them (t =3.201,P =0.033).In addition,elevated temperature and tiredness were found in the model rats.Anterior chamber empyema,iris hyperemia and occlusion of the pupil appeared in the models on the 6th day and peaked on the 12nd day after immunized,with the inflammatory scores of 3.83±0.41.The infiltration of inflammatory cells were seen in anterior chamber,ciliary body and vitreous cavity under the optical microscope in the model rats.Scanning electron microscopy found uneven iris texture,coarse ciliary surface and loosen villi of retinal pigment epithelial (RPE) cells in the model rats.Under the transmission electron microscope,the infiltration of macrophagocytes on the iris,wrinkle sparse of ciliary epithelium,myeloid bodies in retinal Müller cells and vacuolus in mitochondria of RPE cells were exhibited.No obvious abnormality was found in the control rats.Conclusions Lewis rats are autoimmune status following injection of CFA with IRBP(1177-1191) and TB.The morphology and ultrastructure of eyeballs in the EAU rats can explain the finding of eyes.