title: Simple analytic method of 11C-flumazenil metabolite in blood.
abstract: 11C-Flumazenil ((11)C-FMZ) is useful to estimate central benzodiazepine receptors by PET. The binding potential (BP) can be calculated with dynamic PET and continual blood sampling. Because conventional metabolite analysis of plasma samples is complicated and time consuming, a simple method is required to obtain an input function. In this article, a whole blood solvent extraction method was evaluated using data of 13 subjects.
  
  
  METHODS
  The plasma solvent extraction method was estimated in comparison with the thin-layer chromatography (TLC) method. Then, the whole blood solvent extraction method was evaluated in comparison with the plasma solvent extraction method.
  
  
  RESULTS
  Metabolite data analyzed by the plasma extraction method were well correlated with those by the TLC method (r = 0.99). The BP was calculated using both the whole blood extraction data and the plasma extraction data. No difference was observed in all brain regions.
  
  
  CONCLUSIONS
  This simple whole blood solvent extraction method can be applied to clinical BP estimation using (11)C-FMZ.
authors.affiliation: Photon Medical Research Center, Hamamatsu University School of Medicine, Handayama, Hamamatsu, Japan. magata@hama-med.ac.jp
authors.forename: Yasuhiro
authors.initials: Y
authors.lastname: Magata
authors.forename: Takahiro
authors.initials: T
authors.lastname: Mukai
authors.forename: Masafumi
authors.initials: M
authors.lastname: Ihara
authors.forename: Sadahiko
authors.initials: S
authors.lastname: Nishizawa
authors.forename: Haruhiro
authors.initials: H
authors.lastname: Kitano
authors.forename: Koichi
authors.initials: K
authors.lastname: Ishizu
authors.forename: Hideo
authors.initials: H
authors.lastname: Saji
authors.forename: Junji
authors.initials: J
authors.lastname: Konishi
mesh_terms: D000328:Adult; D000368:Aged; D001921:Brain / Q000000981:diagnostic imaging / Q000378:metabolism; D002250:Carbon Radioisotopes / Q000097:blood* / Q000493:pharmacokinetics; D002855:Chromatography, Thin Layer; D005442:Flumazenil / Q000097:blood* / Q000493:pharmacokinetics; D006801:Humans; D008297:Male; D008875:Middle Aged; D010949:Plasma / Q000737:chemistry; D011963:Receptors, GABA-A / Q000032:analysis*; D014055:Tomography, Emission-Computed
chemical_list: D002250:Carbon Radioisotopes; D011963:Receptors, GABA-A; D005442:Flumazenil