| Objective:The present study is to investigate the expression of vascular epithelial growth factor,fibroblast growth factor, heparanase and endostain in retinas with oxygen-induced retinopathy.Methods:Twenty clean neonatal C57BL/6J mice were raised in a hyper oxygen box with a volume percentage of75%+-2%for5days and then returned to the normal air room. Another21matched mice were raised in the normal environment as controls. High molecular weight fluorescein was infused in all the mice on postnatal days12,17and25, afterwards fluorescein angiography was performed and then the mice were sacrificed. The retinas of mice were isolated and prepared and the retinal vessels were examined under a fluorescent microscope. VEGF, bFGF, ET and HPA were detected using real-time PCR. The analysis was used to compare the mRNA levels of these factors.Results:In hyperoxia-treated mice at day12, large areas of the central retina showed no capillaries, and retinal vascular is thinner, the branching is reduced, a small amount of vascular only exist in the peripheral retina. The retinas from control mice in day12and day17developed both superficial and deep vascular layers that extender from the optic disc to the periphery. In hyperoxia-treated mice at day17, the central hypo-perfusion areas were progressively decreased and the radial vessels become tortuous and dilated. A large amount of neovascular tufts appears, at day25, the distribution of blood vessels become uniform than before, but there are still a certain amount of neovascularization. The expression of VEGF, HPA, bFGF mRNA was significantly enhanced in mice from postnatal days12,17and25compared with normal control mice(F=113.608, P=0.000,F=59.235,P=0.000,F=188.493,P=0.000)while the expression of ET mRNA was significantly decreased in hyperoxia-treated mice than the normal ones(F=32.365,P=0.000).conclusion:Exposion to75%concentration of oxygen can induced retinal neovascularization in mice.VEGF,bFGF and HPA may produce a positive effect in angiogensis while ET produces a negative effect. |
