High Affinity 3Himipramine and 3Hparoxetine Binding Sites in Suicide Brains

Specific binding of 3Himipramine & 3Hparoxetine was simultaneously examined in human brains from 11 controls & 11 depressed suicide victims. A single saturable high affinity site was obtained for both radioligands. Age was not related to significant changes in either binding parameter, indicating stability in the brain serotonergic system with increasing age. A significant decrease was found in the maximum number (Bmax) of 3Himipramine binding sites in the hippocampus of the suicides as compared to the control group, without changes in the binding affinity (Kd). When 3Hparoxetine was used as a radioligand, no changes in either Bmax or Kd were detected in any of the brain regions studied. (42 refs.) JA