Deficiency of the BDNF/CREB function made rodents susceptible to depression, while administration of BDNF/CREB produced antidepressant-like effects in models of depression (Chen et al., 2001; Shirayama et al., 2002; Hoshaw et al., 2005; Advani et al., 2009). Here, BDNF is linked to major depressive disorder.