Decreased lymphocyte 3H-paroxetine binding in obsessive-compulsive disorder.

The pathophysiology of obsessive-compulsive disorder (OCD) is mainly focused on the serotonin (5-HT) system and transporter. The presence of this structure in blood lymphocytes prompted us to investigate it, by means of the specific binding of (3)H-paroxetine ((3)H-PAR), in a group of drug-free OCD patients as compared with healthy control subjects matched for sex and age. Lymphocyte membranes and (3)H-PAR binding were carried out according to standard protocols. The results showed that the patients had a statistically significant lower density of (3)H-PAR-binding sites than the control subjects. On one hand, this finding confirms previous data of an abnormal platelet 5-HT transporter in OCD, on the other it provides the possibility to explore the regulation of this structure in this and other disorders, since lymphocytes are nucleate cells. Copyright 2003 S. Karger AG, Basel