The Research Of INOS On The Epithelium's Apoptosis In The Lens Of Diabetic Rats

Objective: Nitrogen monoxidum (NO) is one of the most common oxyradical in tela , height active . A small quantity NO can keep organism physiological drive .But massive NO would oxidative damage to tissue. Nitric oxide synthase (NOS) is the most important synthesis rate-limiting enzyme in corpore. NOS was divided toâ…¢type.â… type andâ…¢type were under Ca²⁺ control, catalysised small quantity NO, kept organism physiological drive.â…¡type named iNOS .Under some stimulus, iNOS actived, catalysised massive NO. We applied STZ to induce diabetic rat modal, and observed the expression of iNOS during diabetic cataract ,and its relative of Caspase-3. To research the pathogenesy of Diabetic cataract and treated rats with drugs to provided certain theory for clinic.Methods: Forty male SD rats about 200g were divided into two parts: one part were for normal group (6 rats ) ,the others were for diabetic model group ( 34 rats) .We applied STZ to induce the diabetic rat modal and affirmed blood glucose was more than 16mmol/L as diabetic rats. The diabetic rats were divided into three groups. Diabetic group (10 rats); Control group (the diabetic rats were treated with INS(10u/kg) ,10 rats);Contrast group (the diabetic rats were treated with PBS(1ml/kg),10 rats).To observe the change of appearance of lens during the whole lab proc. To put each group rats to death on 4 weeks and 8 weeks respectively .Using pathological section and transmission electron microscope to observe minuteness in epithelium of lens .And using immunohistochemistry to observe the iNOS,3-NT,Caspase-3 expression in epithelium of lens. Last using Iamge-pro Plus software to analysis the outcome. And use SPSS13.0 software took statistics analysis to the result, P<0.05 is statistical significance.Results:1. Light microscope :There were no markedly change of appearance in normal group epithelium of lens. In diabetic group, the epithelium of lens had markedly line disord and other apoptosis appearances .The control group had less apoptosis appearances than diabetic group.2. Electron microscope: There were no markedly change on cellular, mitochondria and cell-cell junction in normal group epithelium of lens. In diabetic group, the epithelium of lens had markedly changed in cellular, mitochondria and cell-cell junction apoptosis appearances. The control group had less apoptosis appearances than diabetic group.3. Immunohistochemistry(1) There was no iNOS expression in normal group epithelium of lens. During the hyperglycosemia state, iNOS in epithelium of lens expression were apparently increased.(2)With the increase of iNOS, the expression of NO was increased, NO could bind with superoxide anion in tissue, then created 3-NT, poisonous to epithelium. At the same time ,the expression of Caspase-3 was increased, epithelium became apoptosis.(3)When blood sugar under control, the expression of iNOS was decreased, and the expression of Caspase-3 was decreased too. Contrast to control group and normal group P< 0.05, had statistical significance. Contrast to contrast group ,P>0.05,had no statistical significance. Conclusion: Under continuing hyperglycosemia state, iNOS maybe play an important role in the epithelium's apoptosis process.