Dopamine D1 receptor binding in the striatum of patients with obsessive–compulsive disorder

• Published in: Journal of affective disorders 2009-04, Vol.114 (1), p.321-326
• Main Authors: Olver, James S, O'Keefe, Graeme, Jones, Gareth R, Burrows, Graham D, Tochon-Danguy, Henri J, Ackermann, Uwe, Scott, Andrew, Norman, Trevor R
• Format: Article
• Language: English
• Subjects: Adult; Adult and adolescent clinical studies; Aged; Anxiety disorders. Neuroses; Benzazepines - pharmacokinetics; Biological and medical sciences; Carbon Radioisotopes; Case-Control Studies; Caudate Nucleus - diagnostic imaging; Caudate Nucleus - metabolism; Dopamine Antagonists - pharmacokinetics; Down-Regulation; Female; Humans; Magnetic Resonance Imaging; Male; Medical sciences; Middle Aged; Mood disorders; Obsessive-Compulsive Disorder - diagnostic imaging; Obsessive-Compulsive Disorder - metabolism; Obsessive-compulsive disorders; Positron-Emission Tomography; Psychiatric Status Rating Scales; Psychiatry; Psychology. Psychoanalysis. Psychiatry; Psychopathology. Psychiatry; Putamen - diagnostic imaging; Putamen - metabolism; Receptors, Dopamine D1 - metabolism; Young Adult
• ISSN: 0165-0327; 1573-2517
• DOI: 10.1016/j.jad.2008.06.020

Abstract Background Obsessive–compulsive disorder (OCD) is a chronic anxiety disorder of unknown aetiology. Psychopharmacological studies have suggested a role for the neurotransmitter serotonin however further evidence for serotonin in the aetiology of OCD is conflicted. The authors used positron emission tomography (PET) to examine the binding of the dopamine D1 receptor antagonist [11 C]-SCH23390 to D1 receptors in the striatum of drug-free OCD patients compared with healthy controls. Methods Seven drug-free patients (two drug naïve) with OCD and seven age, gender and education matched healthy controls underwent positron emission tomography with [11 C]-SCH23390. Binding Potentials (BP) at D1 receptors were calculated for the caudate nucleus and putamen. Correlations between BP values for basal ganglia regions and clinical measures were performed in OCD patients. Results The BP for [11 C]-SCH23390 at D1 receptors in OCD patients was significantly reduced in both caudate nucleus (0.59 ±0.06 vs 0.88 ± 0.06, p < 0.05) and putamen (0.89 ± 0.06 vs 1.14 ± 0.06, p < 0.05) compared with healthy controls. No correlations were found between D1 BP and symptom measures. Limitations The main limitations of this study are the small sample size and the PET methodology which does not allow for disaggregation of Bmax and Kd values for D1 receptor binding of [11 C]-SCH23390. Conclusions The finding of downregulation of D1 receptors in the striatum of OCD patients suggests increased nigrostriatal dopaminergic drive in OCD. If confirmed, this finding provides support for trials of novel treatments in OCD based on dopaminergic system blockade.