title: Radiation Dosimetry of (18)F-FPEB in Humans.
abstract: (18)F-3-fluoro-5-[(pyridin-3-yl)ethynyl]benzonitrile ((18)F-FPEB) is a potent and specific radioligand for the metabotropic glutamate receptor subtype 5 (mGluR5). Before undertaking clinical research studies with (18)F-FPEB, we performed studies of human radiation dosimetry.
  
  
  METHODS
  Serial whole-body scans were obtained in 9 healthy human subjects (5 men, 4 women) for 190-440 min after the intravenous administration of (18)F-FPEB. Radiation doses were estimated using the OLINDA/EXM software.
  
  
  RESULTS
  Peak organ doses were to the urinary bladder wall, 0.258 mGy/MBq (0.955 rad/mCi), and gallbladder wall, 0.193 mGy/MBq (0.716 rad/mCi). The effective dose was 0.025 mSv/MBq (0.0922 rem/mCi). The doses to the red marrow and spleen were 0.00797 mGy/MBq (0.0295 rad/mCi) and 0.00709 mGy/MBq (0.0262 rad/mCi), respectively. Reducing the urinary voiding interval to 60 or 90 min lowered the urinary bladder wall dose to 0.0885 mGy/MBq (0.327 rad/mCi) or 0.128 mGy/MBq (0.473 rad/mCi), respectively, and the effective dose to 0.0149 mSv/MBq (0.0551 rem/mCi) or 0.0171 mSv/MBq (0.0634 rem/mCi), respectively.
  
  
  CONCLUSIONS
  Urinary voiding should be performed during (18)F-FPEB studies to minimize radiation exposure to research subjects.
authors.affiliation: Vanderbilt University School of Medicine, Nashville, Tennessee rkessler@uabmc.edu.
authors.forename: Robert M
authors.initials: RM
authors.lastname: Kessler
authors.affiliation: Institute for Neurodegenerative Disorders, New Haven, Connecticut; and.
authors.forename: John
authors.initials: J
authors.lastname: Seibyl
authors.affiliation: Vanderbilt University School of Medicine, Nashville, Tennessee.
authors.forename: Ronald L
authors.initials: RL
authors.lastname: Cowan
authors.affiliation: Psychology, Vanderbilt University School of Arts and Sciences, Nashville, Tennessee.
authors.forename: David
authors.initials: D
authors.lastname: Zald
authors.affiliation: Psychology, Vanderbilt University School of Arts and Sciences, Nashville, Tennessee.
authors.forename: Jacob S
authors.initials: JS
authors.lastname: Young
authors.affiliation: Vanderbilt University School of Medicine, Nashville, Tennessee.
authors.forename: Mohammad Sib
authors.initials: MS
authors.lastname: Ansari
authors.affiliation: Vanderbilt University School of Medicine, Nashville, Tennessee.
authors.forename: Michael G
authors.initials: MG
authors.lastname: Stabin
mesh_terms: D000293:Adolescent; D000328:Adult; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009570:Nitriles / Q000493:pharmacokinetics*; D049268:Positron-Emission Tomography; D011725:Pyridines / Q000493:pharmacokinetics*; D011874:Radiometry; D064529:Receptor, Metabotropic Glutamate 5 / Q000378:metabolism; D051598:Whole Body Imaging; D055815:Young Adult
chemical_list: C527000:3-fluoro-5-((pyridin-3-yl)ethynyl)benzonitrile; D009570:Nitriles; D011725:Pyridines; D064529:Receptor, Metabotropic Glutamate 5
keywords: 18F-FPEB; glutamate; mGluR5; radiation dosimetry