Figure 4. Quantification of PEDF protein in ROP model at different postnatal day ages. ELISA measurements of retinal PEDF protein from selected postnatal days (P) 0 through P18 in RA or in the ROP model. Increased PEDF associated with older developmental age (p=0.005) or the ROP model compared to RA samples (ANOVA, p<0.0001). *Post-hoc testing revealed increased PEDF in the ROP model compared to RA at P11 and P13 (p=0.0041, p=0.0022 respectively). Error bars represent standard errors. Each time point had at least five retinas from different pups taken from at least two different litters.