Figure 3. Time course of fluorescence of a P17 oxygen-induced retinopathy mouse after a retro-orbital injection of fluorescein isothiocyanate dextran (FITC)-dextran. The fluorescence of FITC-dextran in small retinal vessels was too weak at 1 s and 2 s, but the retinal vessels were fully observed at 3 s and could still be seen at 5 h. Original magnification: 50×.