PET brain imaging with [11C](+)McN5652 shows increased serotonin transporter availability in major depression.
BACKGROUND
Alterations in the brain serotonin (5-HT) system have been found in patients with depression. We used the selective 5-HT transporter site ligand [11C](+)McN5652 and positron emission tomography (PET) to examine the hypothesis that alterations in 5-HT transporter levels may be present in selected regions of the brain in depressed patients.


METHODS
Four drug free depressed patients and four healthy control subjects were studied using [11C](+)McN5652 and PET. The distribution volume (DV) ratio of the PET ligand in selected regions of interest (ROIs) compared to cerebellum were calculated for the ROIs.


RESULTS
Patients showed significantly larger DV ratios in the left frontal cortex (P=0.013) and right cingulate cortex (P=0.043) compared to control subjects.


CONCLUSIONS
The sample size was modest with gender differences between the subject groups. The PET agent, [11C](+)McN5652, may have a lower binding affinity for the 5-HT transporter in the cortical regions compared to other brain regions.


CONCLUSIONS
These findings suggest that 5-HT transporter sites may be increased in the frontal and cingulate cortices of depressed patients. These alterations in 5-HT transporter sites may be of pathophysiologic significance in the etiology of depression and its treatment.
Cerebrovascular Research Center, Department of Neurology, University of Pennsylvania School of Medicine, Room 415 Stemmler Hall, Philadelphia, PA 19104-6063, USA. mreivich@mail.med.upenn.edu
Martin
M
Reivich
Jay D
JD
Amsterdam
David J
DJ
Brunswick
Chyng Yann
CY
Shiue
D000328:Adult; D001921:Brain / Q000000981:diagnostic imaging*; D002250:Carbon Radioisotopes; D003865:Major Depressive Disorder / Q000000981:diagnostic imaging*; D004292:Dominance, Cerebral / Q000502:physiology; D005260:Female; D005625:Frontal Lobe / Q000000981:diagnostic imaging; D006179:Gyrus Cinguli / Q000000981:diagnostic imaging; D006801:Humans; D007091:Image Processing, Computer-Assisted; D007546:Isoquinolines; D008297:Male; D008562:Membrane Glycoproteins / Q000378:metabolism*; D026901:Membrane Transport Proteins / Q000378:metabolism*; D008875:Middle Aged; D009419:Nerve Tissue Proteins / Q000378:metabolism*; D049268:Positron-Emission Tomography; D012016:Reference Values; D050486:Serotonin Plasma Membrane Transport Proteins
D002250:Carbon Radioisotopes; D007546:Isoquinolines; D008562:Membrane Glycoproteins; D026901:Membrane Transport Proteins; D009419:Nerve Tissue Proteins; C493230:SLC6A4 protein, human; D050486:Serotonin Plasma Membrane Transport Proteins; C058079:McN 5652