Fig. 3.

VEGF preconditioning up-regulates DG neurogenesis in old mice. (A) Experimental protocol for VEGF induction at progressive ages, with red boxes indicating the onset of a month-long VEGF induction. (B, Left) Representative images of DG vasculature with or without VEGF induced 1 or 3 mo before euthanasia. Ages indicated on the left represent the age of mice at euthanasia. (B, Right) Serial sections of the above stained with DCX. (Scale bar, 100 μm.) Quantification of vessel densities (C) and DCX⁺ cell densities (D). Note, in particular, the marked increase in neurogenesis in 13- and 16-mo-old mice with increased vasculature.