In this section, the authors highlight the pathophysiological processes of depressive disorders which can be targeted by dexmedetomidine, including the immuno-inflammatory mechanisms, the neuro-progression hypothesis, and the role of the Brain-Derived Neurotrophic Factor (BDNF), and the involvement of the adrenergic system in depressive disorder’s pathogenesis. This evidence concerns the gene BDNF and depressive disorder.