Figure 2.

Granule cells born after CCI have accelerated dendritic growth. A, Confocal image of BrdU⁺ cells expressing GFP in POMC-EGFP mice, used to precisely date the birth of cells for morphologic analysis. In this example, BrdU was administered to POMC-EGFP mice 5 d after CCI or sham procedure and perfusion was fixed at 14 d, so that BrdU⁺ cells were 9 d postmitosis. Traced cells are outlined in white. B, Representative images (top) of dendritic tracings of 7-, 9-, and 12-d-old GFP⁺ cells in sham and CCI-treated mice, and the Sholl analyses (bottom) for group data at each time point. In each cohort, CCI increased the number of dendritic branch points of immature cells born during post-traumatic neurogenesis (p = 0.0027¹³). Branches also occurred closer to the cell body in CCI-treated mice in each cohort, which was independent of cell age (p = 0.76¹⁵). C, Representative images of GFP⁺ cells and their dendritic outgrowth. White arrows point to the first dendritic branch points. D–F, GFP⁺ cells from CCI treated mice branched closer to their cell body (***p = 0.0012¹⁶; D), had more cumulative branches (***p = 0.0005¹⁷; E), and had greater total dendritic length (***p = 0.001¹⁸; F).