Fig. 4. Rolipram ameliorates γ-irradiation-induced object recognition memory deficit. (A) The cylinder- and pyramid-shaped objects were presented for 15 min during training the cubeshaped object would be used as a novel object during testing (24 h after testing) . The interactions of the mouse with each object including approaches and sniffing were scored. (B) Vehicle-treated irradiated mice (2 Gy) displayed decreased preference to the novel object compared to sham-irradiated controls during testing at 24 h after training. Treatment of rolipram significantly attenuated the reduction in preference to novel object in vehicle-treated irradiation group. Data are shown as mean ± SEM (*p < 0.05 **p < 0.01) .