Platelet serotonin transporter in children and adolescents with obsessive-compulsive disorder or Tourette's syndrome.
Previous studies of serotonin transporter protein (5HTPR) indexed in platelets by 3H-imipramine demonstrate reduction in children with comorbid obsessive-compulsive disorder (OCD) and Tourette's syndrome (TS).


OBJECTIVE
To use the 5HTPR selective ligand 3H-paroxetine and homogeneous diagnostic groups to reevaluate these findings.


METHODS
Platelet Kinetic binding parameters were evaluated using standard techniques from medication-free child and adolescent patients with OCD (n = 18), with TS (n = 10), and normal controls (n = 19).


RESULTS
Baseline binding capacity (Bmax) was significantly reduced in patients with OCD (1,342 +/- 952 fmol/mg; protein p < .01) compared with normal controls (2,486 +/- 1309 fmol/mg) and TS patients (2,420 +/- 1,069 fmol/mg; p < .05). Among OCD patients who were subsequently treated on an open-label basis with selective serotonin reuptake inhibitor (SSRI), Bmax values at baseline differentiated between responders (1,718 +/- 1,041 fmol/mg) and nonresponders (802 +/- 713 fmol/mg protein; p < .05). Response to SSRI was greatest in patients with a positive family history of OCD. Among responders (n = 10), baseline Yale-Brown Obsessive Compulsive Scale and Bmax were positively correlated (r = .76, p = .01), as was Clinical Global Impression (r = .67, p = .03).


CONCLUSIONS
Platelet 5HTPR capacity (Bmax) is reduced in children and adolescents with OCD, but not in those with TS. 5HTPR may be an indirect measure of basal serotonergic tone.
Sallee
F R
FR
Department of Psychiatry and Behavioral Sciences, Medical University of South Carolina, Charleston 29425, USA.
Richman
H
H
Beach
K
K
Sethuraman
G
G
Nesbitt
L
L
D015057:1-Naphthylamine / Q000031:analogs & derivatives / Q000493:pharmacokinetics / Q000627:therapeutic use; D000293:Adolescent; D000704:Analysis of Variance; D001792:Blood Platelets / Q000378:metabolism*; D002352:Carrier Proteins / Q000097:blood*; D002648:Child; D005260:Female; D006801:Humans; D008297:Male; D008562:Membrane Glycoproteins / Q000097:blood*; D026901:Membrane Transport Proteins; D009419:Nerve Tissue Proteins; D009771:Obsessive-Compulsive Disorder / Q000097:blood* / Q000188:drug therapy; D012701:Serotonin / Q000097:blood*; D050486:Serotonin Plasma Membrane Transport Proteins; D017367:Selective Serotonin Reuptake Inhibitors / Q000493:pharmacokinetics / Q000627:therapeutic use; D020280:Sertraline; D005879:Tourette Syndrome / Q000097:blood* / Q000188:drug therapy
D015057:1-Naphthylamine; D002352:Carrier Proteins; D008562:Membrane Glycoproteins; D026901:Membrane Transport Proteins; D009419:Nerve Tissue Proteins; D012701:Serotonin; D050486:Serotonin Plasma Membrane Transport Proteins; D017367:Selective Serotonin Reuptake Inhibitors; D020280:Sertraline; C493230:SLC6A4 protein, human