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Beta-endorphin responses to metyrapone and dexamethasone in depressed patients
M A Morphy1, G A Fava, R C Pedersen
1Department of Psychiatry, State University of New York, Buffalo.
Abstract:
Controversy continues over the characteristics of beta-endorphin secretion in depression. Beta-endorphin plasma levels were measured in 30 drug-free male patients with a DSM-III-R major depressive disorder and 21 healthy controls. Depressed patients displayed significantly lower beta-endorphin plasma levels in baseline conditions, after the single dose metyrapone test, and after the dexamethasone suppression test. The activation of hypothalamic-pituitary-adrenal (HPA) axis in depression might be due, at least in part, to low levels of beta-endorphin. These results suggest that HPA axis dysregulation in depression may involve peptides other than ACTH.
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