Reduced availability of serotonin transporters in obsessive-compulsive disorder correlates with symptom severity - a [11C]DASB PET study

• Published in: Journal of Neural Transmission Vol. 114; no. 12; pp. 1603 - 1609
• Main Authors: Reimold, M, Smolka, M N, Zimmer, A, Batra, A, Knobel, A, Solbach, C, Mundt, A, Smoltczyk, H U, Goldman, D, Mann, K, Reischl, G, Machulla, H-J, Bares, R, Heinz, A
• Format: Journal Article
• Language: English
• Published: Austria Springer Nature B.V 01.12.2007
• Subjects: Adult; Age Factors; Aniline Compounds; Brain - metabolism; Female; Genotype; Humans; Male; Obsessive compulsive disorder; Obsessive-Compulsive Disorder - metabolism; Positron-Emission Tomography; Serotonin Plasma Membrane Transport Proteins - metabolism; Sex Factors; Smoking; Sulfides
• ISSN: 0300-9564; 1435-1463
• DOI: 10.1007/s00702-007-0785-6

Reduced availability of brainstem serotonin transporters (5-HTT) has been observed in vivo in obsessive-compulsive disorder (OCD). However, results vary and may be influenced by competition with endogenous serotonin. Using positron emission tomography (PET) and [11C]DASB, a specific 5-HTT ligand that showed no competition with serotonin for 5-HTT binding in vitro, we tested the hypothesis that 5-HTT availability is reduced in OCD patients and correlated with OCD severity. METHODS. 5-HTT availability in the thalamus and the midbrain was measured in nine drug-free OCD patients and compared with 19 healthy controls, matched for the individual combination of 5-HTT genotype, gender and smoking status. OCD severity was assessed with the Yale-Brown obsessive compulsive scale (Y-BOCS). RESULTS. 5-HTT availability was significantly reduced in the thalamus and midbrain of OCD patients. Age and 5-HTT in the thalamus explained 83% of OCD severity in patients that were drug-free for at least 1 year. CONCLUSION. This PET study confirms a central role of the serotonergic system, particularly the thalamus in the pathogenesis of obsessive compulsive disorder.