Expression of cyclinD1 in a rat model of oxygen-induced retinopathy

This study sought to elucidate the correlation between cyclinD1 expression and the emergence of neovascularization in oxygen-induced retinopathy (OIR). OIR was induced in Sprague-Dawley 7-day-old neonatal rats exposed to hyperoxia (75% O2) for 5 days, and then returned to room air. Adenosine diphosphatase staining showed that the neovascularization started to emerge at rat age of day 14, and reached a peak at day 17, then gradually decreased and resolved by day 26. Immunohistochemical and immunofluorescence staining revealed that cyclinD1 protein expression was seen in the OIR rats at the age of day 12, then gradually increased and returned to normal levels by day 26. These experimental findings demonstrated that the temporal pattern of cyclinD1 protein expression is consistent with the emergence of retinal neovascularization.