Figure 6.

Social encounter induces c-fos activation in the MOB and DG in a manner that requires juvenile neurogenesis. A, Number of c-fos-positive cells in the MOB increased in wild-type mice exposed to a conspecific in their home cage (Soc, n = 4) compared with mice left socially isolated (Iso, n = 4). B, Social encounter also increased the number of c-fos-positive cells in all subfields of the hippocampus. C, Approximately 30% of NSC labeled with BrdU on PND 36 and 37 induced c-fos expression in the MOB in response to a social encounter. D, Pictures of MOB showing that BrdU cells (green) labeled on PND 36 and 37 express NeuN (red) and induce expression of c-fos (blue) in response to a social encounter in adulthood. E–H, Intracerebroventricular GCV treatment for 30 d during the juvenile period (F_(1,8) = 18.5, p = 0.0026, repeated-measure ANOVA) but not in adulthood decreased c-fos activation in response to a brief social encounter in the MOB (E, G) and hippocampus (F, H). Error bars represent mean ± SEM. *p < 0.05, **p < 0.01, ***p < 0.005. Scale bars, 10 μm.