Analysis of apoptosis in the mouse ON following X-ray irradiation. A, Quantification of apoptotic cell nuclei in the ON of control naive animals in the basal cell layer, intermediate cell layers and sustentacular cell layer (F(17,36) = 8.804, p ≤ 0.0001, n=3 mice). B, Total number of apoptotic cell nuclei throughout the ON for each group (F(5,12) = 2.862, p = 0.0629, n=3 mice). C, TUNEL labeling (green), DAPI (blue), 2 weeks post X-ray irradiation. Dashed line indicates basal lamina. * p ≤ 0.05,** p ≤ 0.01, *** p≤0.001.