Naslov
Brain Regional alpha-[(11)C]Methyl-L-Tryptophan Trapping in Medication-Free Patients With Obsessive-Compulsive Disorder

Autori
Berney, Alexandre ; Leyton, Marco ; Gravel, Paul ; Sibon, Igor ; Sookman, Debbie ; Rosa Neto, Pedro ; Dikšić, Mirko ; Nakai, Akio ; Pinard, Gilbert ; Todorov, Christo ; Okazawa, Hidehiko ; Blier, Pierre ; Nordahl, Thomas Edward ; Benkelfat, Chawki

Izvornik
Archives of general psychiatry (0003-990X) 68 (2011), 7; 732-741

Vrsta, podvrsta i kategorija rada
Radovi u časopisima, članak, znanstveni

Ključne riječi
positron-emission-tomography; methyl-l-tryptophan; serotonin synthesis rate; glucose metabolic rates; borderline personality-disorder; multiple memory-systems; in-vivo; m-chlorophenylpiperazine; transporter-availability; synthesis capacity

Sažetak
The hypothesis of a serotonin (5-hydroxytryptamine [5-HT]) dysfunction in obsessive-compulsive disorder (OCD) stems largely from the clinical efficacy of 5-HT reuptake inhibitors. Serotonergic abnormalities in the unmedicated symptomatic state, however, remain to be fully characterized. Objective was to investigate brain regional 5-HT synthesis, as indexed by positron emission tomography and the alpha-[(11)C]methyl-L-tryptophan trapping constant (K*), in treatment-free adults meeting criteria for OCD. Between-group comparison. Department of Psychiatry and Montreal Neurological Institute, McGill University, and Department of Psychology, McGill University Health Centre, Quebec, Canada. Twenty-one medication-free patients with OCD (15 men with a mean [SD] age of 33.2 [9.3] years and 6 women with a mean [SD] age of 35.8 [7.1] years) and 21 healthy controls matched for age and sex (15 men with a mean [SD] age of 32.9 [10.1] years and 6 women with a mean [SD] age of 36.5.5 [8.6] years). The alpha-[(11)C]methyl-L-tryptophan brain trapping constant K*, which was analyzed with Statistical Parametric Mapping (SPM8) and with proportional normalization (extent threshold of 100 voxels with a peak threshold of P <= .005). Compared with healthy controls, the patients with OCD exhibited significantly greater alpha-[(11)C]methyl-L-tryptophan trapping in the right hippocampus and left temporal gyrus (Brodmann area 20). In the larger subsample of all men, these same differences were also evident, as well as higher K* values in the caudate nucleus. Individual differences in symptom severity correlated positively with K* values sampled from the caudate and temporal lobe of the patients with OCD, respectively. There were no regions where the patients exhibited abnormally low K* values. Volumetric analyses found no morphometric alterations that would account for the group differenees. The results support previous reports of greater striatal and temporal lobe activity in patients with OCD than in healthy controls and suggest that these disturbances include a serotonergic component. Previously reported glucose metabolic disturbances in OCD involving the orbitofrontal and cingulate cortices, in comparison, might reflect postsynaptic changes in the serotonergic system.

Izvorni jezik
Engleski

Znanstvena područja
Temeljne medicinske znanosti

POVEZANOST RADA