BDNF and epilepsy: Although the mechanisms of BDNF in facilitating epileptogenesis (the development of chronic epilepsy) are still uncertain, numerous studies have shown that BDNF expression were up-regulated in various animal models of epilepsy and in human epileptic disorders and that inhibition of BDNF/TrkB function suppressed the development of epilepsy, suggesting that BDNF plays a causal role in epilepsy induction (Kokaia et al., 1995; Binder et al., 1999; Jankowsky and Patterson, 2001; Barton and Shannon, 2005; Heinrich et al., 2011; Grabenstatter et al., 2012; Liu et al., 2013).