Reduced midbrain-pons serotonin transporter binding in patients with obsessive-compulsive disorder.
OBJECTIVE
To evaluate current hypothesis regarding the pathophysiology of obsessive-compulsive disorder (OCD) by studying the serotonin receptor binding in patients with OCD using single photon emission computerized tomography (SPECT).


METHODS
We studied nine patients (four men and five women, age range 21-56 years) fulfilling the DMS-III-R criteria for OCD using SPECT and the serotonin transporter (SERT) tracer (123)I-beta-CIT. SERT binding potential (BP2) was determined by Logan plot derived from seven scans obtained during 10-400 min.


RESULTS
The binding of (123)I-beta-CIT in midbrain-pons was reduced in OCD patients when compared with controls (BP2 0.97 +/- 0.07 vs. 0.84 +/- 0.12, P = 0.011). There was no correlation between BP2 and any of the clinical variables (age at onset, disease duration, and Yale-Brown Obsessive-Compulsive Scale score).


CONCLUSIONS
This study suggests a reduced serotonergic input into the fronto-subcortical circuits in OCD, thereby diminishing the inhibitory regulation of serotonin on these circuits.
Hasselbalch
S G
SG
Neurobiology Research Unit, The Neuroscience Center, Rigshospitalet, Copenhagen, Denmark. sgh@rh.dk
Hansen
E S
ES
Jakobsen
T B
TB
Pinborg
L H
LH
Lønborg
J H
JH
Bolwig
T G
TG
D000328:Adult; D003042:Cocaine / Q000031:analogs & derivatives / Q000493:pharmacokinetics; D005260:Female; D005625:Frontal Lobe / Q000000981:diagnostic imaging / Q000503:physiopathology; D006801:Humans; D007457:Iodine Radioisotopes / Q000493:pharmacokinetics; D008297:Male; D008636:Mesencephalon / Q000000981:diagnostic imaging* / Q000503:physiopathology; D008875:Middle Aged; D009415:Nerve Net / Q000000981:diagnostic imaging / Q000503:physiopathology; D009771:Obsessive-Compulsive Disorder / Q000000981:diagnostic imaging* / Q000503:physiopathology; D011149:Pons / Q000000981:diagnostic imaging* / Q000503:physiopathology; D012016:Reference Values; D050486:Serotonin Plasma Membrane Transport Proteins / Q000378:metabolism*; D013223:Statistics as Topic; D015899:Tomography, Emission-Computed, Single-Photon
D007457:Iodine Radioisotopes; D050486:Serotonin Plasma Membrane Transport Proteins; C069723:2beta-carbomethoxy-3beta-(4-iodophenyl)tropane; D003042:Cocaine