Persistent reduction in brain serotonin1A receptor binding in recovered depressed men measured by positron emission tomography with [11C]WAY-100635

Positron emission tomography ( PET) studies with the selective 5-HT1A receptor ligand, [C-11]WAY-100635, have indicated that the binding potential (BP) of brain 5-HT1A receptors is lowered in unmedicated subjects with acute major depression. However, it is unclear if these changes persist after recovery from depression. To resolve this issue, we used [C-11]WAY-100635 in conjunction with PET imaging to compare 5-HT1A BP in 18 healthy controls and 14 male subjects with recurrent major depression who were clinically recovered and free of antidepressant medication. BP values, derived from a reference tissue model, were analysed by region of interest and statistical parametric mapping. Both analyses showed a widespread and substantial (17%) decrease in 5-HT1A receptor BP in cortical areas in the recovered depressed subjects. In contrast, 5-HT1A BP in the raphe nuclei did not distinguish depressed subjects from controls. Our results suggest a persistent dysfunction in cortical 5-HT1A BP as measured by [C-11]WAY-100635 in recovered depressed men. Lowered 5-HT1A receptor binding availability could represent a trait abnormality that confers vulnerability to recurrent major depression.