Protein levels of Slfn3 (A), villin (B), Glut2 (C), SI (D), and Dpp4 (E) were measured in the jejunum (Jj), upper ileum (IL1), middle ileum (IL2), lower ileum (IL3), and colon (Co) of rats by Western blotting of mucosal lysates. Dpp4 enzyme activity (F) was measured in intestinal rat mucosal samples. A significant difference is indicated if the letter above one error bar is different from that of another (P < .05). Error bars indicate standard errors. RLU indicates relative luminescence units.