Fig. 3. Rolipram exerts a beneficial influence on γ-irradiation-induced decrease of the number of pCREB- (A) Ki-67- (B) and DCX-positive cells (C) in the hippocampal DG. Rolipram (1.25mg/kg) was administered intraperitoneally twice per day for 5 days. All the tissues were collected at 24 h after 2 Gy γ-irradiation. Rolipram treatment significantly increased the number of pCREB- Ki-67- and DCX-positive cells at 24 h after irradiation compared with the vehicle-treated irradiation group. Data are shown as mean ± SEM (*p < 0.05 ***p < 0.001) .