Time-dependent reduction of newborn cells in the HDG subregions and effects of Mn exposure. A, Quantification of BrdU(+) cells in the adult HDG subregions of hilus, SGZ, GCL, and ML of all groups. B, Time-dependent changes of BrdU(+) cell counting in the subregions of control and Mn-exposed HDG. C, Quantification of Sox2/BrdU/DAPI (day 0), DCX/BrdU/DAPI (2 weeks), and NeuN/BrdU/DAPI (4 weeks) triple-labeled cells in the adult HDG subregions of SGZ and GCL of all groups. D, Time-dependent changes of triple-labeled cell counting in the SGZ and GCL of control and Mn-exposed HDG. E, Time-dependent survival rates of BrdU-labeled proliferating cells in the entire HDG of all groups. F, Time-dependent survival rates of triple-labeled cells in the entire HDG of all groups. Data represent mean ± SD, n = 3–4. **p < .01, as compared with the day 0 negative control group; ΔΔp < .01, as compared with the 2-week Ct group; ▲▲p < .01, as compared with the 2-week MnE group; □□p < .01, as compared with the 4-week Ct group.