title: Decreased neurokinin-1 (substance P) receptor binding in patients with panic disorder: positron emission tomographic study with [18F]SPA-RQ.
abstract: BACKGROUND
  Positron emission tomography (PET) can localize and quantify neurokinin-1 (NK(1)) receptors in brain using the nonpeptide antagonist radioligand, [(18)F]SPA-RQ. We sought to determine if patients with panic disorder have altered density of NK(1) receptors in brain because of their history of recurrent panic attacks. We also sought to determine if a drug-induced panic attack releases substance P in brain, as measured by decreased binding of [(18)F]SPA-RQ.
  
  
  METHODS
  Positron emission tomography scans with [(18)F]SPA-RQ were performed in 14 patients with panic disorder and 14 healthy subjects. Of these two groups, 7 patients and 10 healthy subjects were scanned twice, once at baseline and once after injection of doxapram, a drug that induces panic attacks.
  
  
  RESULTS
  NK(1) receptor binding in patients (n = 14) compared with that in healthy subjects (n = 14) was significantly decreased by 12% to 21% in all brain regions. Doxapram effectively produced panic attacks in 6 of 7 patients with panic disorder but only 2 of 10 healthy subjects. Doxapram caused no significant change of [(18)F]SPA-RQ binding in either patients or healthy subjects.
  
  
  CONCLUSIONS
  Although induction of a panic attack has no significant effect on [(18)F]SPA-RQ binding to NK(1) receptors, patients with panic disorder have widespread reduction of NK(1) receptor binding in brain.
authors.affiliation: Molecular Imaging Branch, National Institute of Mental Health, Bethesda, Maryland 20892, USA. FujimuraY@mail.nih.gov
authors.forename: Yota
authors.initials: Y
authors.lastname: Fujimura
authors.forename: Fumihiko
authors.initials: F
authors.lastname: Yasuno
authors.forename: Amanda
authors.initials: A
authors.lastname: Farris
authors.forename: Jeih-San
authors.initials: JS
authors.lastname: Liow
authors.forename: Marilla
authors.initials: M
authors.lastname: Geraci
authors.forename: Wayne
authors.initials: W
authors.lastname: Drevets
authors.forename: Daniel S
authors.initials: DS
authors.lastname: Pine
authors.forename: Subroto
authors.initials: S
authors.lastname: Ghose
authors.forename: Alicja
authors.initials: A
authors.lastname: Lerner
authors.forename: Richard
authors.initials: R
authors.lastname: Hargreaves
authors.forename: H Donald
authors.initials: HD
authors.lastname: Burns
authors.forename: Cheryl
authors.initials: C
authors.lastname: Morse
authors.forename: Victor W
authors.initials: VW
authors.lastname: Pike
authors.forename: Robert B
authors.initials: RB
authors.lastname: Innis
mesh_terms: D000328:Adult; D001921:Brain / Q000000981:diagnostic imaging / Q000378:metabolism* / Q000503:physiopathology; D001931:Brain Mapping; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D016584:Panic Disorder / Q000000981:diagnostic imaging / Q000378:metabolism* / Q000473:pathology / Q000503:physiopathology; D010880:Piperidines; D049268:Positron-Emission Tomography; D011485:Protein Binding / Q000502:physiology; D018040:Receptors, Neurokinin-1 / Q000378:metabolism*; D013777:Tetrazoles
chemical_list: C517420:(2-fluoromethoxy-5-(5-trifluoromethyltetrazol-1-yl)benzyl)(2-phenylpiperidin-3-yl)amine; D010880:Piperidines; D018040:Receptors, Neurokinin-1; D013777:Tetrazoles