实验性头颅侧向旋转脑弥漫轴索损伤神经丝蛋白亚单位含量变化

目的： 探讨实验性头颅侧向旋转脑弥漫轴索损伤（ＤＡＩ）中神经丝（ＮＦ）蛋白亚单位含量变化． 方法： ＳＤ大鼠２４只，等分为三个损伤组（伤后２， １２， ２４ ｈ）及一个对照组，对损伤组制作头颅侧向旋转脑ＤＡＩ模型． 用Ｗｅｓｔｅｒｎ 印迹技术进行免疫活性定量测定，以检测全部损伤及对照组大鼠脑干组织ＮＦ蛋白亚单位ＮＦ６８的含量． 结果： 脑干ＮＦ６８含量在伤后２ ｈ 倾向下降，１２ ｈ 显著减少，继续降低至２４ ｈ；其降解产物ＮＦ５６， ＮＦ５２在伤后２ ｈ～１２ ｈ 趋于增加，２４ ｈ 提高至显著水平． 结论： 头颅侧向旋转ＤＡＩ后脑干神经丝产生磷酸化反应，引起ＮＦ６８水解，造成ＮＦ６８含量减少． 提示神经丝蛋白亚单位水解是ＤＡＩ中神经丝结构破坏的重要原因．

The content change of neurofilament protein subunit in experimental brain diffuse axonal injury by lateral head rotation

AIM: To explore the content change of neurofilament (NF) protein subunits in experimental brain diffuse axonal injury (DAI) by lateral head rotation. METHODS: Twenty four SD rats were equally divided into three injury groups (2, 12, 24 h post injury) and one control group. The models of DAI were produced in all the rats of injury groups by lateral head rotation. Quantitative immunoactivity measurements by Western blot technique were used to measure the content of NF68 (a kind of NF protein subunits) in tissues from the brain stem in all the injured and control rats.RESULTS: NF68 content in brain stem tended to decrease 2 h after injury, decreased significantly 12 h after injury and continued its decrease up to 24 h after injury. NF56 and NF52, as the breakdown products of NF68, increased 2 h~12 h after injury, and reached a significantly higher level 24 h after injury. CONCLUSION: Phosphorolysis occurs within the brain stem in DAI induced by lateral head rotation, causes NF68 breakdown, resulted in NF68 decrease. Neurofilament protein subunits breakdown is an important reason for structural destruction of neurofilaments in DAI.