RESUMEN
Objective To establish hyperoxia retinopathy in premature rat model with SpragueDawley (SD),observe the pathological changes of angiogenesis and expression of vascular endothelial growth factor (VEGF),and compare the effect of bevacizumab periocular injection and intravitreal injection of retinopathy of premature rats.Methods Ninety preterm rat retinopathy models were randomly divided into 3 groups:high oxygen group,retrobalbar injection group,and vitreous cavity group (n =30 per group);36 healthy rats were chosen as the normal control group.Each group were randomly selected 10 rats 'right eyes to make retinal flat mount to observe the right eye retina vascular morphology;10 resections of right eyes were embedded in paraffin,and stained with hematoxylin eosin (HE);the number of right eye of retinal neovascularization was observed;the right eye RNA was extracted,and reverse-transcription polymerase chain reaction (RT-PCR) was used to detect the expression of VEGF.Results The normal group showed retinal vessels were around a reflection of distribution,good branch,shape rules,and clear structure.Intravitreous neovascularization occurred in the high oxygen group and peribulbar injection group.Retinal vascular endothelial cells in the high oxygen group were increased significantly compared to the normal group (P ＜ 0.05).The visible clusters of red blood cells in the periocular injection group and vitreous group were decreased compared to the high oxygen group (P ＜ 0.05),but no significant difference between the periocular injection group and vitreous group (P ＞ 0.05).The expressions of VEGF mRNA and HE staining had a consistent trend.Conclusions Bevacizumab inhibited the expression of VEGF that was increased in premature rats in hyperoxia retinopathy.The effects of bevacizumab periocular injection and intravitreal injection were similar,but the former was more secure than the latter.