title: Fractionation Spares Mice From Radiation-Induced Reductions in Weight Gain But Does Not Prevent Late Oligodendrocyte Lineage Side Effects.
abstract: To determine the late effects of fractionated versus single-dose cranial radiation on murine white matter.
  
  
  
  Mice were exposed to 0 Gy, 6 × 6 Gy, or 1 × 20 Gy cranial irradiation at 10 to 12 weeks of age. Endpoints were assessed through 18 months from exposure using immunohistochemistry, electron microscopy, and electrophysiology.
  
  
  
  Weight gain was temporarily reduced after irradiation; greater loss was seen after single versus fractionated doses. Oligodendrocyte progenitor cells were reduced early and late after both single and fractionated irradiation. Both protocols also increased myelin g-ratio, reduced the number of nodes of Ranvier, and promoted a shift in the proportion of small, unmyelinated versus large, myelinated axon fibers.
  
  
  
  Fractionation does not adequately spare normal white matter from late radiation side effects.
authors.affiliation: Department of Environmental Medicine, University of Rochester School of Medicine and Dentistry, Rochester, New York.
authors.forename: Sage
authors.initials: S
authors.lastname: Begolly
authors.affiliation: Department of Neuroscience, University of Rochester School of Medicine and Dentistry, Rochester, New York; Department of Pharmacology and Physiology, University of Rochester School of Medicine and Dentistry, Rochester, New York.
authors.forename: Peter G
authors.initials: PG
authors.lastname: Shrager
authors.affiliation: Department of Neuroscience, University of Rochester School of Medicine and Dentistry, Rochester, New York.
authors.forename: John A
authors.initials: JA
authors.lastname: Olschowka
authors.affiliation: Department of Environmental Medicine, University of Rochester School of Medicine and Dentistry, Rochester, New York; Department of Radiation Oncology, University of Rochester School of Medicine and Dentistry, Rochester, New York.
authors.forename: Jacqueline P
authors.initials: JP
authors.lastname: Williams
authors.affiliation: Department of Neuroscience, University of Rochester School of Medicine and Dentistry, Rochester, New York; Department of Neurology, University of Rochester School of Medicine and Dentistry, Rochester, New York. Electronic address: Kerry_OBanion@URMC.Rochester.edu.
authors.forename: M Kerry
authors.initials: MK
authors.lastname: O'Banion
mesh_terms: D000818:Animals; D019070:Cell Lineage / Q000528:radiation effects*; D002478:Cells, Cultured; D016371:Cranial Irradiation / Q000009:adverse effects*; D019583:Dose Fractionation, Radiation; D004307:Dose-Response Relationship, Radiation; D051379:Mice; D009836:Oligodendroglia / Q000473:pathology / Q000528:radiation effects*; D059351:Organ Sparing Treatments / Q000379:methods; D058958:Organs at Risk / Q000528:radiation effects; D011829:Radiation Dosage; D011835:Radiation Protection / Q000379:methods; D015430:Weight Gain / Q000528:radiation effects*; D066127:White Matter / Q000473:pathology / Q000528:radiation effects*