Figure 5.

Running increases network activity in the temporal GCL and accelerates neuronal maturation. A, Representative images of Arc expression (red) in the septal and temporal dentate gyrus of running mice. NeuN immunofluorescence is shown in blue. Note the similar level of Arc expression (red) in the septal and temporal GCL. Scale bar, 100 μm. B, Paired analysis of Arc expression in sections obtained from the same running mice. No significant differences were found (p = 0.73, Wilcoxon's test; n = 9). C, Running increases Arc expression in the temporal GCL. The bars combine the data shown in Figures 1E and 5B. **p < 0.01, Kruskal–Wallis followed by post hoc Conover's test. D, Examples of newborn DGCs (white) at 21 dpi in the septal and temporal dentate gyrus of the same running mouse. Note the similar degree of maturation in both regions. Sections were counterstained with DAPI (blue). Scale bar, 50 μm. E, Dendritic segments of 21 dpi neurons from the septal and temporal dentate gyrus in sedentary and running mice, as indicated. Scale bar, 2 μm. F, Running increases spine density in newborn DGCs of the temporal dentate gyrus. Spine count analysis in 21 dpi neurons, with n = 45 total (septal plus temporal) fragments taken from four running mice. Data for sedentary mice are the same as that shown in Figure 4G. **p < 0.01, ANOVA with Bonferroni's post hoc test. G, Newborn DGCs (green) at 21 dpi in the temporal dentate gyrus of a running mouse expressing both Cb (red) and NeuN (blue). Images are single optical planes for each channel and their overlay. Scale bar, 10 μm. H, Running increases Cb expression in 21 dpi neurons of the temporal hippocampus. The bars show the proportion of GFP⁺ cells that display Cb expression, with n = 462 neurons from eight running mice compared with data shown in Figure 4J for sedentary mice. ***p < 0.001, two-way ANOVA with Bonferroni's post hoc test. All bars denote mean ± SEM.