Newborn rats model of oxygen fluctuations-induced retinopathy

Objective The authors developed a rat model of retinal neovascularization by repeated fluctuations of inhaled oxygen between hyperoxia(80%) to hypoxia(10%).MethodsTwenty-four newborn SD rats were randomly divided into oxygen and control groups.The control group was kept in room environment.The oxygen group was kept in the oxygen concentration that was alternated between 80% to 10% every 24 hours for 7 days.The status of retinal vasculature was observed after birth in both oxygen group and control group at 12 days.ADP enzymohistochemistry stain method of retinal stretched preparation was used to observe the change of retinal blood vessels.HE staining was used for counting the number of nuclei extending from retinal area into vitreous to identify extraretinal neovascularization.The immunohistochemistry method was used to measure the expression of VEGF in the retina.Results Compared with control group,the oxygen had abnormal changes in retinal vascular,the ganglion cells arranged abnormally with the decrease in number.The numbers of nuclei extending from the retinal area into the vitreous area in oxygen group were significantly higher compared with the control(P0.001).The expression of VEGF in the oxygen group was significantly stronger than that of the control group.Conclusions High-amplitude fluctuations oxygen was associated with the development of retinal neovascularization in the retinopathy.VEGF expression was significantly increased in the oxygen fluctuations-induced neovascularized retina.The method was confirmed that SD rat model of retinopathy was induced by 80 to 10% oxygen fluctuations.