Sleep EEG and the nocturnal secretion of cortisol and testosterone in 12 male patients (mean age 46.4 +/- 11.26 years) with major endogenous depression were investigated concomitantly during acute depression, before treatment and after recovery and drug cessation. Testosterone concentration increased after remission, while cortisol secretion decreased. Sleep EEG disturbances remained unchanged in remitted patients. The data suggest that a blunted testosterone and an elevated cortisol secretion are state markers of acute depression, which normalize independently from sleep structure. An interaction between the hypothalamic-pituitary-gonadal axis and the limbic-hypothalamic-pituitary-adrenocortical axis appears likely.