GSK3B and major depressive disorder: This is a surprising result, because in the case of chronic stress—which is the main factor in the etiopathogenesis of depression—there is a reduction in phosphorylated Gsk-3β and β-catenins in the PFc, as well as in the administration of the serotonin reuptake inhibitor and citalopram, which restore the levels of these proteins to the control state [35].