NGF and stroke disorder: Exercising animals with stroke-induced brain injury increases the expression of other neurotrophic factors, such as BDNF, NGF, HGF, HIF-1, and bFGF, which regulate neuronal survival and differentiation as well as synaptic plasticity in the hippocampus and cerebral cortex (Gonez-Pinilla et al. 1998, Ang et al. 2003, Ding et al., 2004b; Endres et al. 2003, Kim et al. 2005).