title: Severe diffuse axon injury in chronic alcoholic rat medulla oblongata following a concussion blow.
abstract: OBJECTIVE
  We investigated the axonal morphological changes and expression of both tau protein and β-APP following concussion to the medulla oblongata, in a rat model of chronic alcoholism.
  
  
  METHODS
  Fifty-nine male Sprague-Dawley rats were randomly divided into EtOH, EtOH-TBI and control groups (water group, water-TBI group). To establish chronic alcoholic rats, rats were intragastrically given edible spirituous liquor twice daily. Rats also received a blow on the occipital tuberosity with an iron pendulum. Morphological changes and expression of tau and β-APP proteins in the medulla oblongata were examined.
  
  
  RESULTS
  (a) Nerve fibre thickening and twisting were observed in alcoholic rats, with nerve fibre changes becoming more significant following a concussion blow, which leads to some nerve fibres fracturing. (b) Transmission electron microscopy revealed that the nerve fibre myelin became loosened and displayed lamellar separation, which became more significant following concussion. (c) The integral optical density (IOD) sum value of β-APP of the EtOH-TBI group was lower than that in the EtOH group (P < 0.05); the Tau IOD sum value of the EtOH-TBI group was higher than that in the EtOH group (P < 0.05).
  
  
  CONCLUSIONS
  (a) Chronic alcoholism caused nerve fibre and neuronal morphology damage in the rat medulla oblongata, with structural damage becoming more significant following concussion. (b) Concussion changed the expression of β-APP and tau protein in chronic alcoholic rat medulla oblongata, suggesting that chronic alcoholism can lead to severe axonal injury following a concussion blow. (c) The effect of chronic alcoholism may be synergistic the concussion blow to promote animal injury and death.
authors.affiliation: Corresponding author: Department of Forensic Medicine, Shantou University Medical College, Xinling Road 22, Shantou City, Guangdong Province 515031, China; xjyustu@gmail.com.
authors.forename: Jianming
authors.initials: J
authors.lastname: Luo
authors.forename: Guang
authors.initials: G
authors.lastname: Chen
authors.forename: Lai
authors.initials: L
authors.lastname: Wei
authors.forename: Hong
authors.initials: H
authors.lastname: Qian
authors.forename: Xiaoping
authors.initials: X
authors.lastname: Lai
authors.forename: Dian
authors.initials: D
authors.lastname: Wang
authors.forename: Junyao
authors.initials: J
authors.lastname: Lv
authors.forename: Xiaojun
authors.initials: X
authors.lastname: Yu
mesh_terms: D000437:Alcoholism / Q000150:complications* / Q000378:metabolism / Q000473:pathology*; D016564:Amyloid beta-Protein Precursor / Q000096:biosynthesis; D000818:Animals; D001924:Brain Concussion / Q000150:complications* / Q000473:pathology*; D002908:Chronic Disease; D020833:Diffuse Axonal Injury / Q000150:complications* / Q000378:metabolism / Q000473:pathology*; D008526:Medulla Oblongata / Q000293:injuries / Q000378:metabolism / Q000473:pathology* / Q000648:ultrastructure; D009186:Myelin Sheath / Q000473:pathology / Q000648:ultrastructure; D051381:Rats; D016875:tau Proteins / Q000096:biosynthesis
chemical_list: D016564:Amyloid beta-Protein Precursor; D016875:tau Proteins