ACTH and multisteroid responses to corticotropin-releasing factor in depressive illness: relationship to multisteroid responses after ACTH stimulation and dexamethasone suppression.

One hundred micrograms of ovine-corticotropin releasing factor (o-CRF) was administered intravenously to eight unmedicated patients with severe endogenous depression. Responses of immunoreactive (ir)-ACTH and the adrenal glucocorticosteroids corticosterone (B), 11-deoxycortisol (S), cortisol (F) and cortisone (E) were measured and compared with those following synthetic corticotropin stimulation and dexamethasone suppression. A comparative evaluation of the three pituitary--adrenal function tests suggests that hypersecretion of ir-ACTH and adrenal corticosteroids (B, S, F, and E) in depression reflects a central dysfunction rather than an altered responsiveness of the pituitary or adrenal glands. The data illustrate that the o-CRF paradigm is a valuable instrument to further support the hypothesis that a limbic--hypothalamic overdrive is the basic mechanism underlying exaggerated adrenocortical output in the endogenous subgroup of depressed patients.