Effect of light deprivation on expression of extended vascular endothelial growth factor and neovascularization in retina of neonatal rats.

OBJECTIVE The aim of this study is to analyze the effect of light deprivation on the expression of vascular endothelial growth factor (VEGF) and neovascularization in the retina of neonatal rats. MATERIALS AND METHODS Thirty-six neonatal SD rats (male and female) were used in this study. These rats were numbered randomly and assigned into 3 groups (12 rats in each group), ie. 10-day group (routine feeding after birth, eyeball enucleation on 10th day), 14-day group (routine feeding after birth, eyeball enucleation on 14th day) and light deprivation group (routine feeding within 1st week after birth, feeding with light deprivation within 2nd week after birth, eyeball enucleation on 14th day). The expression level of VEGF mRNA was measured by RT-PCR, and the percentage of the retinal vascular area was calculated by PAS staining, and the number of vascular endothelial cells was counted with a microscope in a double-blind manner. RESULTS It was found that the expression levels of VEGF mRNA and the number of vascular endothelial cells in 10-day group and light deprivation group were significantly higher than 14-day group (p < 0.05), while the difference between the 10-day group and light deprivation group was not significant. The percentage of retinal vascular area in the 10-day group and light deprivation group was significantly lower than 14-day group (p < 0.05), while the difference between the 10-day group and the light deprivation group was not significant. CONCLUSIONS The light deprivation delayed the growth of neovessels in the retina.