Serotonin transporters in obsessive-compulsive disorder: a positron emission tomography study with [(11)C]McN 5652.
BACKGROUND
Serotonergic abnormalities have been hypothesized to contribute to obsessive-compulsive disorder (OCD). This study examined whether brain serotonin transporter (SERT) availability is altered in OCD using positron emission tomography (PET) and the SERT PET radiotracer [(11)C]McN 5652.


METHODS
Eleven OCD subjects, free of psychiatric medications and comorbid depression, and 11 matched healthy control subjects underwent PET scans following injection of [(11)C]McN 5652 and magnetic resonance imaging (MRI) scans. Total distribution volumes (V(T)) were derived by kinetic analysis (one tissue compartment model) using the arterial input function. Two measures of SERT availability were computed: binding potential (BP) and specific to nonspecific partition coefficient (V(3)"). Groups were compared using region of interest (ROI) analysis and voxelwise analysis of spatially normalized parametric maps; ROIs were selected based on their relatively high SERT density and included subcortical (dorsal caudate, dorsal putamen, ventral striatum, midbrain, thalamus) and limbic (hippocampus, amygdala, anterior cingulate cortex) regions.


RESULTS
No significant group differences were observed in [(11)C]McN 5652 BP or V(3)" in the ROIs. No significant group differences were detected in the voxelwise analysis of BP or V(3)" maps.


CONCLUSIONS
OCD without comorbid depression, may not be associated with major changes in SERT availability in subcortical and limbic regions.
Simpson
H Blair
HB
Department of Psychiatry, Columbia University, College of Physicians and Surgeons, New York, New York, USA.
Lombardo
Ilise
I
Slifstein
Mark
M
Huang
Henry Yiyun
HY
Hwang
Dah Ren
DR
Abi-Dargham
Anissa
A
Liebowitz
Michael R
MR
Laruelle
Marc
M
D000293:Adolescent; D000328:Adult; D001921:Brain / Q000033:anatomy & histology / Q000000981:diagnostic imaging / Q000378:metabolism*; D001931:Brain Mapping; D002250:Carbon Radioisotopes; D002352:Carrier Proteins / Q000378:metabolism*; D016022:Case-Control Studies; D003710:Demography; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D007546:Isoquinolines / Q000493:pharmacokinetics; D007700:Kinetics; D008279:Magnetic Resonance Imaging; D008297:Male; D008562:Membrane Glycoproteins / Q000378:metabolism*; D026901:Membrane Transport Proteins; D008875:Middle Aged; D009419:Nerve Tissue Proteins; D009771:Obsessive-Compulsive Disorder / Q000000981:diagnostic imaging / Q000378:metabolism*; D012702:Serotonin Antagonists / Q000493:pharmacokinetics; D050486:Serotonin Plasma Membrane Transport Proteins; D014055:Tomography, Emission-Computed / Q000379:methods*
D002250:Carbon Radioisotopes; D002352:Carrier Proteins; D007546:Isoquinolines; D008562:Membrane Glycoproteins; D026901:Membrane Transport Proteins; D009419:Nerve Tissue Proteins; C493230:SLC6A4 protein, human; D012702:Serotonin Antagonists; D050486:Serotonin Plasma Membrane Transport Proteins; C058079:McN 5652