Dopamine D-1 and D-2 receptor binding sites in brain samples from depressed suicides and controls

Dopamine D-1 and D-2 receptors were measured (by saturation binding of [H-3]SCH23390 and [H-3]raclopride) in caudate; putamen and nucleus accumbens, obtained at post-mortem from suicide victims with a firm retrospective diagnosis of depression, and matched controls. There were no differences in the number or affinity of D-1 or D-2 receptors between suicides who had been free of antidepressants for at least three months prior to death, and controls. Increased numbers and decreased affinity of D-2 receptors were however found in each brain region of antidepressant-treated suicides. We argue that these increases are related to concurrent treatment with neuroleptics rather than a direct effect of antidepressants. Increased numbers of D-1 receptors in antidepressant-treated suicides were seen only in nucleus accumbens. This increase could not be clearly attributed to neuroleptics and may be related to antidepressant treatment. (C) 1997 Elsevier Science B.V.