Fig. 7.

Chronic DPP-4 inhibition increases the number, the mean volume, and the arborization of calbindin+ interneurons and it promotes neuroblast differentiation in the piriform cortex of diabetic rats. a Density of CB+ interneurons and, b-c representative microphotographs of CB+ staining in the PC of control vs. linagliptin-treated GK rats (n = 9). d Mean volume and, e-f illustrating microphotographs of CB+ interneurons in the PC of control vs. linagliptin-treated GK rats. g Neuronal arborization and, h-i illustrating microphotographs of CB+ interneurons in the PC of the compared groups (n = 9). j Total number of DCX+ immature neurons and, k percent of double-stained DCX/NeuN+ "differentiating" neurons (n = 8). Two-tailed, unpaired t-test. The data are means ±S.E.M., * p < 0.05, ** p < 0.01