The Experimental Study On The Role Of NFκBp65, NOS2 In Pathogenesis Of Xerophthalmia

Objective: Establish animal models with xerophthalmia, including: groupe A ,Six rabbits which were given a casein-base vitamin A-deficient diet for 6 months and groupe B, Six male rabbits which were castrated for 3 months,and investigate the expression and role of NFKBp65,NOS2 in cornea, conjunctiva, lacrimal gland of rabbits with experimental xerophthalmia.Material and Methods: groupe A: 6 rabbits were given a casein-base vitamin A-deficient diet for 6 months, another 6 rabbits were given a normal diet as the control team, groupe B: 6 male rabbits were castrated for 3 months , another 6 rabbits were not castrated as the control ones and they were both given normal diet,then we got xerophthalmia models and controls.Schirmer's I test,tear film break-up time(BUT) and corneal fluorescence staining were performed on the eyes before and after the experinent.The animals were executed after that ,small pieces of corneas, conjunctivas, lacrimal glands of xerophthalmia models and normal controls were obtained right then.Parts of them were observed by microscope,parts were disposed by immunohistochemical staining to detect the expression of NFκBp65,NOS2.Results: Fluorescence staining of the cornea was positive in model groups after the experiment while it was negative in normal controls.Schirmer's I test,tear film break-up time were significantly lower in both groups after the experiment than the normal controls.The pathological changes of the xerophthalmia models were characterized by cornea ulceration,keratinization of the corneal epithelium,loss of globlet cells from the conjunctival epithelium,lymphocte soakage in lacrimal glands,lacrimal glands atrophy,and so on.The expression of NFκBp65,NOS2 in the models was prominently higher than in the normal controls(F <0.01). NFκBp65's expression was mainly endocellular, whereas NOS2 was extracellular.Conclusions: Vitamin A deficiency and the low level of testosterone are the main causes of xerophthalmia. The immunological inflammation related to NFκBp65,NOS2 in corneas, conjunctivas,lacrimal glands may be the main pathological process leading toxerophthalmia.Postgraduate student: Chao Liu (ophthalmology) Directed by Prof. Chan - fu Wang...