title: Decreased dopamine D2 receptor binding in the anterior cingulate cortex in schizophrenia.
abstract: BACKGROUND
  The clinical efficacy of dopamine D2 receptor antagonism on the psychotic symptoms of schizophrenia has been widely demonstrated. However, most in vivo imaging studies have not been able to detect significant changes in striatal D2 receptors in schizophrenia. On the other hand, a number of studies have reported abnormalities in the cerebral cortex of schizophrenia. The aim of this study was to examine the extrastriatal D2 receptors of patients with schizophrenia.
  
  
  METHODS
  Eleven drug-naive male patients with schizophrenia were examined with positron emission tomography using carbon 11-labeled FLB 457. Symptoms were assessed using the Brief Psychiatric Rating Scale. Eighteen healthy controls were used for comparison. Region-of-interest analysis was performed using the reference tissue method, and binding potential (BP) was used for the index of dopamine D2 receptor binding.
  
  
  RESULTS
  The BP value was significantly lower, by about 12.5%, in the anterior cingulate cortex in drug-naive patients with schizophrenia than in healthy controls. A significant negative correlation was observed between BP in the anterior cingulate cortex and the positive symptom score on Brief Psychiatric Rating Scale.
  
  
  CONCLUSIONS
  The lower BP values indicate fewer D2 receptors in the anterior cingulate cortex in patients with schizophrenia. Alterations in D2 receptor function in the extrastriatal region may underlie the positive symptoms of schizophrenia.
authors.affiliation: Division of Advanced Technology for Medical Imaging, National Institute of Radiological Sciences, 9-1, Anagawa 4-Chome, Inage-ku, Chiba-shi, 263-8555 Japan. suhara@nirs.go.jp
authors.forename: Tetsuya
authors.initials: T
authors.lastname: Suhara
authors.forename: Yoshiro
authors.initials: Y
authors.lastname: Okubo
authors.forename: Fumihiko
authors.initials: F
authors.lastname: Yasuno
authors.forename: Yasuhiko
authors.initials: Y
authors.lastname: Sudo
authors.forename: Makoto
authors.initials: M
authors.lastname: Inoue
authors.forename: Tetsuya
authors.initials: T
authors.lastname: Ichimiya
authors.forename: Yoshifumi
authors.initials: Y
authors.lastname: Nakashima
authors.forename: Kazuhiko
authors.initials: K
authors.lastname: Nakayama
authors.forename: Shuji
authors.initials: S
authors.lastname: Tanada
authors.forename: Kazutoshi
authors.initials: K
authors.lastname: Suzuki
authors.forename: Christer
authors.initials: C
authors.lastname: Halldin
authors.forename: Lars
authors.initials: L
authors.lastname: Farde
mesh_terms: D000328:Adult; D001931:Brain Mapping; D018492:Dopamine Antagonists / Q000493:pharmacokinetics; D006179:Gyrus Cinguli / Q000000981:diagnostic imaging / Q000503:physiopathology*; D006801:Humans; D008297:Male; D011569:Psychiatric Status Rating Scales; D011759:Pyrrolidines / Q000493:pharmacokinetics; D017448:Receptors, Dopamine D2 / Q000502:physiology*; D012016:Reference Values; D012457:Salicylamides / Q000493:pharmacokinetics; D012559:Schizophrenia / Q000000981:diagnostic imaging / Q000503:physiopathology*; D012565:Schizophrenic Psychology; D014055:Tomography, Emission-Computed
chemical_list: D018492:Dopamine Antagonists; D011759:Pyrrolidines; D017448:Receptors, Dopamine D2; D012457:Salicylamides; C065065:FLB 457