FIG. 5.

The hippocampal neurogenesis is impaired following spinal cord injury (SCI). (A) Approximate positions of the hippocampal anatomical structures are shown in an atlas overlay. The insert shows the dentate gyrus (DG) area for digital images captured at 20× magnification, which included granular layer (GL), subgranular zone (SGZ), and hilus. (B) Proliferating cells stained by bromo-deoxyuridine (BrdU) were significantly decreased in the moderate and severe SCI groups, compared with sham mice. *p < 0.05 vs. sham group. n = 8–9. (C) Immature neurons stained by doublecortin (DCX) were significantly decreased in the mild, moderate, and severe SCI groups, compared with sham-operated group. **p < 0.01, ***p < 0.001 vs. sham group. n = 8–9. (D and E) Representative images showed BrdU+ and DCX+ cells along with nuclear staining (4',6-diamidino-2-phenylindole, blue) in the hippocampal DG sub-region in sham, mild, moderate, and severe SCI mice. Scale bar = 250 μm. (F–I) Number of co-localized BrdU+/DCX+ and BrdU+/NeuN+ cells showed a significant decrease in proliferating immature (F) and mature (H) neurons in mice with mild, moderate, and severe SCI. The percentage of BrdU+/DCX+ in total proliferating cells (BrdU+) did not reach the significance while the percentage of proliferating mature neurons (BrdU+/NeuN+) was significantly decreased in the moderate and severe SCI groups, compared with the sham-operated group. *p < 0.05, **p < 0.01, ***p < 0.001 vs. sham group. n = 8–9. Color image is available online at www.liebertpub.com/neu