Fig. 1: Schematic representation of the hypothalamic–pituitary–adrenocortical (HPA) axis. Stimulatory (+) and inhibitory (–) actions of neural inputs to brain regions involved in HPA system regulation and the sites of corticosteroid regulation are shown. The sites at which antidepressants have stimulatory actions on the glucocorticoid receptor (GR), mineralocorticoid receptor (MR), or both, are indicated. IL = interleukin, GABA = γ-aminobutyric acid, Ach = acetylcholine, CRH = corticotropin-releasing hormone, VP = vasopressin, ACTH = corticotropin, NE = norepinephrine, E = epinephrine, 5HT = serotonin, DA = dopamine.