title: Dopamine D2 receptor imaging in Gilles de la Tourette syndrome.
abstract: OBJECTIVE
  To examine postsynaptic dopamine D2 receptors in Tourette syndrome (TS).
  
  
  METHODS
  Seventeen patients and a control group were investigated using single photon emission computed tomography (SPECT) and iodobenzamide (123I-IBZM).
  
  
  RESULTS
  In neuroleptic treated patients (n = 7) 123I-IBZM-binding was significantly reduced compared to both normal controls (P < 0.0001) and unmedicated patients (P < 0.001). In unmedicated patients (n = 10) mean binding ratio did not differ from that of control group. Patients in advanced stages of the disease, however, revealed significantly reduced relative striatal binding compared to patients in the early stages (P<0.005) and normal controls (P<0.0001).
  
  
  CONCLUSIONS
  The results lend further support to the hypothesis that the dopamine receptor is involved in TS pathology. During the natural course of the disease tics often improve in early adulthood. It is suggested that this spontaneous recovery from tics may be associated with reduced receptor binding capacity.
authors.affiliation: Department of Neurology, Medical School Hannover, Germany.
authors.forename: K R
authors.initials: KR
authors.lastname: Müller-Vahl
authors.forename: G
authors.initials: G
authors.lastname: Berding
authors.forename: H
authors.initials: H
authors.lastname: Kolbe
authors.forename: G J
authors.initials: GJ
authors.lastname: Meyer
authors.forename: H
authors.initials: H
authors.lastname: Hundeshagen
authors.forename: R
authors.initials: R
authors.lastname: Dengler
authors.forename: W H
authors.initials: WH
authors.lastname: Knapp
authors.forename: H M
authors.initials: HM
authors.lastname: Emrich
mesh_terms: D000293:Adolescent; D000328:Adult; D001549:Benzamides / Q000378:metabolism / Q000493:pharmacokinetics; D001667:Binding, Competitive / Q000502:physiology; D002648:Child; D003287:Contrast Media; D003342:Corpus Striatum / Q000000981:diagnostic imaging* / Q000378:metabolism*; D018492:Dopamine Antagonists / Q000627:therapeutic use; D005260:Female; D005625:Frontal Lobe / Q000000981:diagnostic imaging* / Q000378:metabolism*; D006801:Humans; D008297:Male; D008875:Middle Aged; D010868:Pimozide / Q000627:therapeutic use; D011759:Pyrrolidines / Q000378:metabolism / Q000493:pharmacokinetics; D017448:Receptors, Dopamine D2 / Q000378:metabolism*; D012720:Severity of Illness Index; D015899:Tomography, Emission-Computed, Single-Photon; D005879:Tourette Syndrome / Q000175:diagnosis* / Q000188:drug therapy / Q000378:metabolism*
chemical_list: D001549:Benzamides; D003287:Contrast Media; D018492:Dopamine Antagonists; D011759:Pyrrolidines; D017448:Receptors, Dopamine D2; D010868:Pimozide; C055743:3-iodo-2-hydroxy-6-methoxy-N-((1-ethyl-2-pyrrolidinyl)methyl)benzamide