Figure 4. Immunohistochemistry for phosphorylated cAMP response element-binding protein (pCREB) in the dentate gyrus of control, vehicle-treated, and Bacopa monnieri extract (BME)-treated mice. Strong and abundant pCREB-positive nuclei are observed in the subgranular zone in BME-treated mice. GCL, granule cell layer; ML, molecular layer; PL, polymorphic layer. Scale bar=50 µm. The relative number of pCREB-positive nuclei in the dentate gyrus per section for each group are shown as a percentage of the value (n=5 per group; ^aP<0.05, vs. control group; ^bP<0.05, vs. vehicle-treated group). Data are presented as mean±SEM.