Posttraumatic stress disorder and platelet serotonin measures

The role of serotonin (5HT) in the pathophysiology of posttraumatic stress disorder (PTSD) has been suggested by the overlap in clinical symptoms betw een PTSD and psychiatric conditions in which a serotonin dysfunction is imp licated, as well as by the therapeutic efficiency of 5HT-related drugs (ant idepressants, selective serotonin reuptake inhibitors and monoamine oxidase inhibitors) in alleviating symptoms in PTSD. In the present study, the blo od platelet, which has been proposed as a peripheral model for the central serotonergic neurons, has been used to search for alterations in 5HT mechan isms in PTSD. Platelet serotonin level and kinetics of serotonin transporte r and monoamine oxidase (MAO-B) were assessed in 63 combat-related PTSD pat ients and 43 sex and age-matched control subjects. A significant reduction in maximal velocity of platelet MAO-B (approx. 30%), with no changes in the enzyme affinity was observed in our patient sample. Conversely, no alterat ions in kinetic parameters (V-max, K-m) of platelet serotonin transporter, as well as in platelet 5HT level, were found in the PTSD group. (C) 2000 El sevier Science Ltd. All rights reserved.