title: Reduced serotonin-1A receptor binding in social anxiety disorder.
abstract: BACKGROUND
  Results from studies in serotonin-1A (5-HT1A) knockout mice and previous positron emission tomography (PET) studies in humans imply a role for 5-HT1A receptors in normal state anxiety as well as in certain anxiety disorders. The objective of this study was to investigate 5-HT1A receptor binding potential (BP) in social anxiety disorder (SAD).
  
  
  METHODS
  Using PET and [carbonyl-11C]WAY-100635, we compared a homogeneous group of 12 unmedicated, male SAD patients with 18 healthy control subjects (HC). A multivariate ANOVA with all regional BP values as dependent variables, age and four radiochemical variables as covariates was performed.
  
  
  RESULTS
  We found a significantly lower 5-HT1A BP in several limbic and paralimbic areas but not in the hippocampus (p = .234) of SAD patients. The difference in 5-HT1A binding was most significant in the amygdala (-21.4%; p = .003). There was also a more than 20% lower 5-HT(1A) BP of SAD patients in the anterior cingulate cortex (p = .004), insula (p = .003), and dorsal raphe nuclei (p = .030).
  
  
  CONCLUSIONS
  The lower 5-HT1A binding in the amygdala and mesiofrontal areas of SAD patients is consistent with 1) preclinical findings of elevated anxiety in 5-HT1A knockout mice, 2) a previous PET study in healthy volunteers showing an inverse correlation between 5-HT1A BP and state anxiety, and 3) another human PET study in patients with panic disorder showing reduced 5-HT1A binding, thus corroborating the potential validity of 5-HT1A receptors as targets in the treatment of human anxiety disorders.
authors.affiliation: Department of General Psychiatry, Medical University of Vienna, Vienna, Austria. rupert.lanzenberger@meduniwien.ac.at
authors.forename: Rupert R
authors.initials: RR
authors.lastname: Lanzenberger
authors.forename: Markus
authors.initials: M
authors.lastname: Mitterhauser
authors.forename: Christoph
authors.initials: C
authors.lastname: Spindelegger
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Wadsak
authors.forename: Nikolas
authors.initials: N
authors.lastname: Klein
authors.forename: Leonhard-Key
authors.initials: LK
authors.lastname: Mien
authors.forename: Alexander
authors.initials: A
authors.lastname: Holik
authors.forename: Trawat
authors.initials: T
authors.lastname: Attarbaschi
authors.forename: Nilufar
authors.initials: N
authors.lastname: Mossaheb
authors.forename: Julia
authors.initials: J
authors.lastname: Sacher
authors.forename: Thomas
authors.initials: T
authors.lastname: Geiss-Granadia
authors.forename: Kurt
authors.initials: K
authors.lastname: Kletter
authors.forename: Siegfried
authors.initials: S
authors.lastname: Kasper
authors.forename: Johannes
authors.initials: J
authors.lastname: Tauscher
mesh_terms: D000328:Adult; D001921:Brain / Q000000981:diagnostic imaging; D001923:Brain Chemistry / Q000502:physiology; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D010698:Phobic Disorders / Q000000981:diagnostic imaging / Q000378:metabolism* / Q000523:psychology; D010879:Piperazines; D049268:Positron-Emission Tomography; D011569:Psychiatric Status Rating Scales; D011725:Pyridines; D044282:Receptor, Serotonin, 5-HT1A / Q000378:metabolism*; D012702:Serotonin Antagonists
chemical_list: D010879:Piperazines; D011725:Pyridines; D012702:Serotonin Antagonists; D044282:Receptor, Serotonin, 5-HT1A; C090413:N-(2-(4-(2-methoxyphenyl)-1-piperazinyl)ethyl)-N-(2-pyridinyl)cyclohexanecarboxamide