PRESERVATION OF HYPOTHALAMIC-PITUITARY-ADRENAL AXIS FAST-FEEDBACK RESPONSES IN DEPRESSION

Depression is associated with overactivity of the hypothalamic-pituita ry-adrenal (HPA) axis, which may be attributable to defective negative feedback. Fast feedback is the earliest phase of this, and has previo usly been suggested to be abnormal. A total of 30 physically healthy v olunteers, 15 patients with DSM-III-R major depression and an age- and sex-matched control group received a standardized challenge of hydroc ortisone (5 mu g kg(-1) min(-1)) or placebo over a period of 1 h. ACTH 1-39 responses to hydrocortisone challenge did not differ significantl y between healthy volunteers and patients with major depression. The f ast-feedback response to hydrocortisone challenge is preserved in majo r depression when ACTH is measured directly.