Figure 4. Changes in the density of surface LECs in fixed-eye sections. The LEC densities in the central zone of unirradiated control and X- irradiated lens sections were determined by counting the DAPI stained nuclei per mm of lens surface (see Methods). X-irradiation was at 3 months. The surface LEC nuclei/mm densities decreased with age (p<0.001 between unirradiated 3-month and 25 month-old mice lenses). The p values shown are for a comparison of the LEC densities in X-irradiated and age-matched controls at 7 months, 12 months, and 14 months using a single tailed Mann–Whitney test. The error bars are for the standard error of the mean. Each bar represents the mean for 6–8 mice.