The memory enhancing effect of Dangui-Jakyak-San (DJS). (A) To test memory enhancing effect of DJS, passive avoidance test was conducted. DJS (50, 100, 200, and 400 mg/kg/day) was administered for 14 days. Passive avoidance task was conducted 1 h after the last treatment. Data are presented as mean ± S.E.M (n = 10/group). *P < 0.05, compared with control group (one-way ANOVA followed by Student Newman-Keuls’s post-hoc test). (B) In a separate experiment, BrdU staining was conducted to test effect of DJS on neurogenesis. Mice were treated with DJS (100 mg/kg/day), and sacrificed 1 h after the last administration. BrdU was administered at 13th day (50 mg/kg, i.p., 3 times by 2 h interval). Arrows indicate immunopositive cells. Data are presented as mean ± S.E.M (n = 6/group). *P < 0.05, compared with control group (Student t-test). Bar = 50 μm.