title: Use of [18F]fluorodeoxyglucose and the ATLAS small animal PET scanner to examine cerebral functional activation by whisker stimulation in unanesthetized rats.
abstract: OBJECTIVE
  Stroking the whiskers of a rat is known to increase cerebral blood flow and glucose utilization in the somatosensory cortex. We sought to determine whether this activation could be detected with small animal PET and 2-[F]fluoro-2-deoxyglucose ([F]FDG).
  
  
  METHODS
  Awake rats were coinjected with [F]FDG and [C]deoxyglucose ([C]DG), and during the uptake of the tracers, five, 10, or 15 whiskers on one side of the face were continuously stimulated. At the end of uptake, the animal was killed and imaged with the Advanced Technology Laboratory Animal Scanner small animal PET scanner. Carbon-14 autoradiography was then performed on brain sections obtained from each animal, and increases in tracer uptake in the somatosensory cortex were compared with those determined with PET.
  
  
  RESULTS
  Both methods showed increases in [F]FDG and [C]DG uptake in the somatosensory cortex in response to the stimulation of as few as five whiskers. However, the magnitude of activation determined from the PET images was less than that from autoradiography due to the lower spatial resolution of the PET scanner.
  
  
  CONCLUSIONS
  Advanced Technology Laboratory Animal Scanner small animal PET imaging with [F]FDG can be used to assess neuronal functional activity in vivo.
authors.affiliation: Department of Positron Emission Tomography bNuclear Medicine, Clinical Center cLaboratory of Cerebral Metabolism dSection on Neuroadaptation and Protein Metabolism, National Institute of Mental Health, National Institutes of Health, Bethesda, Maryland, USA.
authors.forename: Laura
authors.initials: L
authors.lastname: Ravasi
authors.forename: Kazuaki
authors.initials: K
authors.lastname: Shimoji
authors.forename: Marisa L
authors.initials: ML
authors.lastname: Soto-Montenegro
authors.forename: Takanori
authors.initials: T
authors.lastname: Esaki
authors.forename: Jurgen
authors.initials: J
authors.lastname: Seidel
authors.forename: Louis
authors.initials: L
authors.lastname: Sokoloff
authors.forename: Kathleen
authors.initials: K
authors.lastname: Schmidt
mesh_terms: D000818:Animals; D001345:Autoradiography / Q000379:methods; D001786:Blood Glucose / Q000032:analysis / Q000378:metabolism; D002250:Carbon Radioisotopes; D003847:Deoxyglucose; D019788:Fluorodeoxyglucose F18; D008297:Male; D049268:Positron-Emission Tomography / Q000379:methods*; D019275:Radiopharmaceuticals; D051381:Rats; D013003:Somatosensory Cortex / Q000000981:diagnostic imaging* / Q000378:metabolism*; D014738:Vibrissae / Q000502:physiology*
chemical_list: D001786:Blood Glucose; D002250:Carbon Radioisotopes; D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18; D003847:Deoxyglucose