Interestingly, some studies have shown that antidepressant-like effects observed in mouse models of depression after chronic administration of antidepressants were reversed by TrkB antagonist injection (Boulle et al. 2016; Ma et al. 2016; Yasuda et al. 2014) and that inhibition of TrkB signaling blocked the effects of antidepressants (Saarelainen et al. 2003). Here, NTRK2 is linked to major depressive disorder.