Dopamine transporter binding in depressed patients with anhedonia.

Central dopaminergic dysfunction has been widely proposed as a common neurobiological correlate of the psychopathological expression of anhedonia. The dopamine transporter (DAT) is a predominantly presynaptic receptor that may play a critical role in the pathophysiology of dopaminergic transmission. The aim of our study was to evaluate DAT binding in a population of depressed patients with anhedonia. Single photon emission computed tomography (SPECT) with the radiotracer DATSCAN was used to evaluate DAT binding in 11 depressed patients with anhedonia and 9 healthy comparison subjects. Compared with healthy subjects, patients showed significantly lower DAT binding. No significant correlation was found between DAT binding ratios and scores on administered psychometric tests. These findings suggest an alteration in DAT density in depressed patients with anhedonia that may be a primary susceptibility factor or a secondary phenomenon to reduced dopamine concentration in the synaptic cleft.