Plasma levels of 3-methoxy-4-hydroxyphenylglycol (MHPG) were measured in
51 depressed patients and 43 normal control subjects. There were
significantly higher plasma MHPG levels in the combined patient group with
current or past melancholia (N = 28) than in nonmelancholic (N = 12) or
dysthymic (N = 11) patients, in unipolar melancholic (N = 16) versus
bipolar melancholic (N = 4) patients, and in patients with a major
depressive episode who failed to suppress cortisol after the dexamethasone
suppression test (N = 24) versus patients with normal suppression (N = 16).
Anxiety symptoms correlated significantly with plasma MHPG levels. These
results substantiate previous evidence that dysregulation of the
hypothalamic-pituitary-adrenal axis and sympathetic nervous system occur
together in a subgroup of depressed patients.