CEREBROSPINAL-FLUID BIOGENIC-AMINES IN OBSESSIVE-COMPULSIVE DISORDER,TOURETTES-SYNDROME, AND HEALTHY CONTROLS

To examine the role of noradrenergic, dopaminergic, and serotonergic m echanisms in the pathobiology of obsessive compulsive disorder (OCD) a nd Tourette's syndrome (TS), concentrations of tyrosine (TYR), norepin ephrine (NE), 3-methoxy-4-hydroxyphenylethylene glycol (MHPG), homovan illic acid (HVA), tryptophan (TRP), and 5-hydroxyindoleacetic acid (5- HIAA) were measured in the lumbar cerebrospinal fluid (CSF) of 39 medi cation-free OCD patients, 33 medication-free TS patients, and 44 healt hy volunteers. CSF TYR concentrations were reduced (p < .05) in the OC D patients compared to the healthy subjects. CSF NE in TS patients was 55% higher than in healthy controls (p < .001) and 35% higher than in OCD patients (p < .001). After covarying for height, CSF HVA levels w ere reduced (p < .05) in the OCD group compared to TS patients but not compared to the normal volunteers. No mean differences in CSF MHPG, T RP, and 5HIAA were observed in this study across the three groups. The CSF NE data support the hypothesis that noradrenergic mechanisms are involved in the pathobiology of TS. Alterations in the balance of nora drenergic, dopaminergic, and serotonergic systems are likely involved in the pathobiology of OCD.