Regional serotonin levels in brain: a comparison of depressive suicides and alcoholic suicides with controls.

The levels of 5-hydroxytryptamine have been measured in 33 areas of the human brain and these levels compared in depressed suicides, in alcoholic suicides, and in controls. The values obtained for control brains ranged from 5.3 mumole 5-HT/kg wet weight in substantia nigra to 0.4 mumole 5-HT/kg wet weight in frontal gray. No significant differences were found among diagnostic groups in any of the areas studied.