Intracellular cyclic adenosine monophosphate (cAMP) signaling activated by brain-derived neurotrophic factor (BDNF) has been shown to be a pivotal player in neuroplasticity and MDD; moreover, studies have demonstrated that treatment with antidepressants can alter the expression of components of this signaling pathway in rodents [5-7]. The gene discussed is BDNF; the disease is major depressive disorder.