The hypotheses to be tested were, whether metyrapone exerts potentiating effects during a standard antidepressant therapy and whether an earlier onset-of-action and an improved overall and sustained treatment response can be achieved. Since GR/MR distribution as well as 11β-HSD-1 activities are subject to sexual dimorphism in humans, the sample was prospectively stratified for gender and balanced for treatment with two selected serotonergic antidepressants, allowing further analysis of gender effects and neuroendocrine treatment effects.