新型弥漫性轴索损伤动物模型的建立

A new rat model of diffuse axonal injury and the injury mechanism

目的研制一联合直线加速损伤和旋转加速损伤的弥漫性轴索损伤（DAI）致伤装置。方法自制联合两种损伤的致伤装置，使大鼠受450g钢棒于0．9m高处坠落打击致伤后，即刻发生90度瞬间旋转，其角加速度峰值为1．36×10^5md／s^2，用时约34ms；对大鼠伤后行为学及病理学进行分析评价。结果大鼠伤后出现昏迷时间的延长（11.9±3．6）min，与对照组（6．5±1．3）min比较差异有统计学意义（P〈0．05），伤后病理学改变符合中重型DAI特征。结论实验装置利用联合损伤机制在较小力学参数下建立了大鼠DAI模型，且具良好的稳定性和重复性。

Objective To develop a clinically-relevant model of diffuse axonal injury （DAI）, a new rat model of DAI was established by combining linear and angular accelerations and the injury mechanism was explored. Methods According to the combined injury mechanism, an experimental facility was designed. This model let rat rotate 90 degrees after undergoing an impact by dropping a 450 g weight from a height of 0.9 m. The maximum of rotational acceleration was 1.36 × 105 rad/s^2 and rotating time was about 34 ms. Behavioral and pathologic changes of the rats were evaluated. Results Following injury, experimental rats took longer to regain consciousness （ 11.9 ± 3.6 ） min than control rats [ （ 6.5 ± 1.3 ） min, P 〈 0.01 ]. Behavioral and pathologic observations showed rats conformed to the characteristics of moderate/severe DAI. Conclusion This experimental facility can reproduce DAI with mild levels of both forms of acceleration combined. Its repeatability and stability are good.