title: Development of a small-animal focal brain irradiation model to study radiation injury and radiation-injury modifiers.
abstract: OBJECTIVE
  Our aim was to establish an effective small-animal focal brain radiation model for research on brain injuries.
  
  
  METHODS
  Groups of up to six rats were exposed to a range of doses from 120-40 Gy, at 10 intervals of a 6 MeV electron beam. Open-field motor functions and water maze learning-memory tests were performed after the irradiation at two-week intervals. Morphological changes were detected through repeated magnetic resonance imaging (MRI) monthly and were compared with the histopathological findings to determine if they predicted late microscopic changes.
  
  
  RESULTS
  The development of necrosis proved to be dose-dependent. 120 Gy resulted in serious deterioration within 4 weeks in all rats. Localized necrosis in one hemisphere was detected 2 months after the irradiation with ≥ 70 Gy, and 3 months after 40-60 Gy consistent for all animals. The Morris water maze (MWM) tests proved to be the most sensitive tool for the early detection of a brain functional impairment. MRI screening provided useful information on the development of radiation necrosis, which defined the time point for histological examinations.
  
  
  CONCLUSIONS
  The described method permits accurate dose delivery to a definite part in one hemisphere of the brain for six rats at a time. Following complex examinations, a dose of 40 Gy and a follow-up time of 4 months are proposed for investigations on neuroradiation modifiers.
authors.affiliation: Department of Oncotherapy, Faculty of Medicine, University of Szeged, Szeged, Hungary. katalin.hideghety@gmail.com
authors.forename: Katalin
authors.initials: K
authors.lastname: Hideghéty
authors.forename: Imola
authors.initials: I
authors.lastname: Plangár
authors.forename: Imola
authors.initials: I
authors.lastname: Mán
authors.forename: Gábor
authors.initials: G
authors.lastname: Fekete
authors.forename: Zoltán
authors.initials: Z
authors.lastname: Nagy
authors.forename: Gábor
authors.initials: G
authors.lastname: Volford
authors.forename: Tünde
authors.initials: T
authors.lastname: Tőkés
authors.forename: Emilia
authors.initials: E
authors.lastname: Szabó
authors.forename: Zoltán
authors.initials: Z
authors.lastname: Szabó
authors.forename: Kitti
authors.initials: K
authors.lastname: Brinyiczki
authors.forename: Petra
authors.initials: P
authors.lastname: Mózes
authors.forename: István
authors.initials: I
authors.lastname: Németh
mesh_terms: D000818:Animals; D001921:Brain / Q000187:drug effects / Q000473:pathology / Q000503:physiopathology / Q000528:radiation effects*; D004307:Dose-Response Relationship, Radiation; D008279:Magnetic Resonance Imaging; D008297:Male; D011833:Radiation Injuries, Experimental / Q000473:pathology / Q000503:physiopathology; D011837:Radiation-Protective Agents / Q000494:pharmacology; D051381:Rats; D017207:Rats, Sprague-Dawley
chemical_list: D011837:Radiation-Protective Agents