Plasma measures of B-endorphin-like immunoreactivity in depressives and other psychiatric subjects.

We report the utilization of a very sensitive radioimmunoassay for plasma B-END, which has enabled us to examine the suppressibility of B-END-like material, under dexamethasone challenge, on a population of depressed patient~. We have found that B-END-like material in plasma is suppressed by dexamethasone in a psychiatric control population, whereas suppression is less likely in endogenously depressed patients. There also appears to be a dissociation between cortisol and B-END measures (tested at 4:00 PM) in the endogenously depressed group.