For the in vivo experiments, a total of 102 adult female Sprague-Dawley rats were used. In the preliminary PEDF neuroprotection dose-finding experiments, groups comprised six rats/treatment (i.e., 12 eyes/treatment): (1) Intact, (2) ONC+vehicle (PBS; 0 μg/μL PEDF), (3) 0.2 μg/μL PEDF, (4) 0.5 μg/μL PEDF, (5) 1 μg/μL PEDF, (6) 1.5 μg/μL PEDF, and (7) 2 μg/μL of PEDF dissolved in 5 μL of sterile saline. In further experiments, six rats/treatment (i.e., 12 eyes/treatment) were used for the FluroGold (FG) backfilling of RGC experiments, while a separate six rats/treatment (i.e., 12 eyes and ON/treatment) were used for growth associated protein-43 (GAP43) immunostaining in the ON and glial fibrillary acidic protein (GFAP)/PEDF immunostaining in the retina. In these experiments, treatment groups comprised: (1) Intact, (2) ONC+PBS, (3) ONC+cAMP, (4) ONC+PEDF, and (5) ONC+cAMP+PEDF.