INCREASED DENSITY OF MU-OPIOID RECEPTORS IN THE POSTMORTEM BRAIN OF SUICIDE VICTIMS

The biochemical status of mu-opioid receptors in suicide was evaluated by [H-3]DAGO specific binding in postmortem human brains from 15 suicide victims and 15 controls. The density (B-max) in frontal cortex and thalamus was directly correlated with age. In the frontal cortex and caudate but not in the thalamus of suicide victims the density of mu-opioid receptors was 36-39% higher than in controls. K-D values in suicide victims were similar to those in control group (range 1.4-2.2 nM). The results suggest an increase of mu-opioid receptors in suicide associated to some brain areas showing the mu(2)-opioid receptor subtype.