This increase in ONL may have the potential to preserve photoreceptors, highlighting the therapeutic potential of these PARP inhibitors in retinal degeneration (ONL thickness, untreated: 36.29 ± 1.62 SEM n = 7, 100 nM Olaparib: 51.40 ± 1.8 SEM n = 6, 3 nM BMN-673: 56.87 ± 8.85 SEM n = 5, 10 nM 3AB: 53.08 ± 7.55 SEM n = 5 p < 0.0001; photoreceptor row numbers, untreated: 8.29 ± 0.12 SEM n = 5, 100 nM Olaparib: 9.40 ± 0.37 SEM n = 5, 3 nM BMN-673: 10.48 ± 0.21 SEM n = 5, 10 nM 3AB: 9.37 ± 0.30 SEM n = 5 *p < 0.05, ***p < 0.001) (Fig. 2E–H, K, L). This evidence concerns the gene PARP1 and retinal degeneration.