In that study we demonstrated that TrkB-signaling is necessary for behavioral sensitization after nerve injury, which agreed with many other studies that applied BDNF peripherally or administered intrathecal BDNF or TrkB scavengers (Shu et al., 1999; Thompson et al., 1999; Fukuoka et al., 2001; Groth and Aanonsen, 2002; Coull et al., 2005; Bao et al., 2014). Here, BDNF is linked to injury.