title: X-ray therapy promotes structural regeneration after spinal cord injury in a rat model.
abstract: OBJECTIVE
  This study aims to investigate the therapeutic effects and mechanisms of x-ray treatment on rats following spinal cord injury (SCI).
  
  
  METHODS
  Forty-six female Sprague-Dawley rats were subjected to spinal cord injury using the modified Allen weight-drop method. The animals were randomly divided into six groups. Two of the animal groups were irradiated with 10 Gy at the lesion site; another two groups were irradiated with 20 Gy; and the last two groups without irradiation were regarded as the sham group. One of the each of two animal groups was euthanized at different time points at 4 and 12 weeks, respectively, after irradiation. Spinal cord calluses were assessed using kinology and electrophysiology and histology methods.
  
  
  RESULTS
  In all of the groups, the neurofilament (NF) counts at 14 weeks were found to be higher than that at 6 weeks after SCI. Both 10-Gy irradiated and 20-Gy irradiated groups were higher than those of the sham group at each time point (P < 0.05). The myelin basic protein (MBP) count decreased at 14 weeks after SCI in the irradiated groups (P < 0.05) but increased at 14 weeks in the sham group (P < 0.05). Furthermore, the MBP count of the irradiated groups was lower than that of the sham group at 14 weeks (P < 0.05). The glial fibrillary acidic protein (GFAP) and Nogo-A counts at 14 weeks were higher than those at 6 weeks in all the groups (P < 0.05), and there was no statistical significance with kinology and electrophysiology tests in all groups.
  
  
  CONCLUSIONS
  A self-repair mechanism exists after spinal cord injury, which lasts at least 14 weeks. X-ray therapy promotes the regeneration of the spinal cord system after injury.
authors.affiliation: Department of Orthopaedics, the Second Affiliated Hospital of Soochow University, Suzhou, 215004, China.
authors.forename: Dong
authors.initials: D
authors.lastname: Liu
authors.affiliation: Department of Orthopaedics, the Seventh People's Hospital of Suzhou, Suzhou, 215151, China.
authors.forename: Jun
authors.initials: J
authors.lastname: Hua
authors.affiliation: Department of Orthopaedics, the Second Affiliated Hospital of Soochow University, Suzhou, 215004, China.
authors.forename: Qi-rong
authors.initials: QR
authors.lastname: Dong
authors.affiliation: Department of Orthopaedics, the Second Affiliated Hospital of Soochow University, Suzhou, 215004, China.
authors.forename: Yong-ming
authors.initials: YM
authors.lastname: Sun
authors.affiliation: Department of Orthopaedics, the First Affiliated Hospital of Soochow University, Suzhou, 215006, China.
authors.forename: Min-feng
authors.initials: MF
authors.lastname: Gan
authors.affiliation: Department of Orthopaedics, the Second Affiliated Hospital of Soochow University, Suzhou, 215004, China. 3022077769@qq.covvvvvvm.
authors.forename: Yi-xin
authors.initials: YX
authors.lastname: Shen
authors.affiliation: Department of Orthopaedics, the Second Affiliated Hospital of Soochow University, Suzhou, 215004, China.
authors.forename: Zhi-hai
authors.initials: ZH
authors.lastname: Fan
authors.affiliation: Department of Orthopaedics, the Second Affiliated Hospital of Soochow University, Suzhou, 215004, China.
authors.forename: Peng
authors.initials: P
authors.lastname: Zhang
mesh_terms: D000818:Animals; D004195:Disease Models, Animal; D004307:Dose-Response Relationship, Radiation; D005260:Female; D005904:Glial Fibrillary Acidic Protein / Q000378:metabolism; D007382:Intermediate Filaments / Q000473:pathology / Q000528:radiation effects; D004676:Myelin Basic Protein / Q000378:metabolism; D009416:Nerve Regeneration / Q000528:radiation effects*; D000070798:Nogo Proteins / Q000378:metabolism; D011879:Radiotherapy Dosage; D017207:Rats, Sprague-Dawley; D013119:Spinal Cord Injuries / Q000473:pathology / Q000503:physiopathology / Q000532:radiotherapy*
chemical_list: D005904:Glial Fibrillary Acidic Protein; D004676:Myelin Basic Protein; D000070798:Nogo Proteins