Attenuated serotonin transporter association between dorsal raphe and ventral striatum in major depression

• Published in: Human brain mapping 2014-08, Vol.35 (8), p.3857-3866
• Main Authors: Hahn, Andreas, Haeusler, Daniela, Kraus, Christoph, Höflich, Anna S., Kranz, Georg S., Baldinger, Pia, Savli, Markus, Mitterhauser, Markus, Wadsak, Wolfgang, Karanikas, Georgios, Kasper, Siegfried, Lanzenberger, Rupert
• Format: Article
• Language: English
• Subjects: Adult; Benzylamines; Biological and medical sciences; Brain - diagnostic imaging; Brain - metabolism; Brain Mapping; Carbon Radioisotopes; Depressive Disorder, Major - diagnostic imaging; Depressive Disorder, Major - metabolism; dorsal raphe nucleus; Dorsal Raphe Nucleus - diagnostic imaging; Dorsal Raphe Nucleus - metabolism; Female; General aspects; Humans; interregional association; Investigative techniques, diagnostic techniques (general aspects); major depression; Male; Medical sciences; Nervous system; Planification. Prevention (methods). Intervention. Evaluation; Positron-Emission Tomography; Public health. Hygiene; Public health. Hygiene-occupational medicine; Radiodiagnosis. Nmr imagery. Nmr spectrometry; Radiopharmaceuticals; Regression Analysis; Serotonin Plasma Membrane Transport Proteins - metabolism; serotonin transporter; Signal Processing, Computer-Assisted; Smoking; ventral striatum; Ventral Striatum - diagnostic imaging; Ventral Striatum - metabolism
• ISSN: 1065-9471; 1097-0193
• DOI: 10.1002/hbm.22442

Suffering from anhedonia, patients with major depressive disorder (MDD) exhibit alterations in several parts of the serotonergic neurotransmitter system, which are in turn involved in reward processing. However, previous investigations of the serotonin transporter (SERT) focused on regional differences with varying results depending on the clinical syndrome. Here, we aimed to describe the serotonergic system of MDD patients on a network level by evaluating SERT associations across brain regions. Twenty medication free patients with major depression and 20 healthy controls underwent positron emission tomography using the radioligand [11C]DASB. SERT binding potentials (BPND) were quantified voxel‐wise with the multilinear reference tissue model 2. In addition, SERT BPND was extracted from the dorsal raphe nucleus (DRN) as an indicator of midbrain serotonergic neurotransmission. Whole‐brain linear regression analysis was applied to evaluate the association of DRN SERT bindings to those in projection areas, which was followed by ANCOVA to assess differences in interregional relationships between patients and controls. Although both groups showed widespread positive correlations, group differences were restricted to decreased SERT associations between the DRN and the ventral striatum (right and left respectively: t = 5.85, P