目的 探讨利用抓力( grasp strength, GS)-运动诱发电位(motor evoked potential,MEP)方法对大鼠脑干锥体束损伤后产生的运动功能障碍进行定量研究。 方法 雄性 SD 大鼠 30 只,分为 1. 25m 致伤组、2. 25 m 致伤组和正常组,采用经典 Marmarou 模型制作锥体束部位的创伤性轴索损伤模型,致伤组均于损伤后 1、3、5、7、14、28、42 d 对大鼠进行肢体 GS 信号和 MEP 波幅检测,3 组大鼠均于麻醉后相应时间进行对照检测。 结果 致伤组随损伤程度的增加,MEP 波幅和最大 GS 下降比例明显增大;两个高度下 GS 与 MEP 测量值具有明显正相关性。 损伤程度较小时,前期 MEP 比较敏感,后期 MEP 不敏感;损伤程度较大时,前期与后期 MEP 变化均较为敏感。 结论 采用 GSMEP 联合评估可以为锥体束损伤后产生的运动功能障碍程度的定量评价提供数据支持。

Objective To quantitatively investigate the motor dysfunction after brain stem pyramidal tract injury in rats by grasp strength (GS)-motor evoked potential (MEP). Methods Thirty healthy male SD rats were randomly divided into 1.25 m injury group, 2.25 m injury group and normal group. The classical marmarou model was used to make the traumatic axonal injury model of pyramidal tract. In injury group, the limb GS signal and MEP were detected at 1st , 3rd, 5th , 7th , 14th, 28th and 42nd day after injury, and the control test was carried out at the corresponding time after anesthesia. Results With the increase in injury degree, the MEP amplitude and maximum GS decreased significantly in injury group. The measured values of GS and MEP under two heights had obvious positive correlation. When the damage degree was relatively small, MEP was more sensitive at early stage, but MEP was not sensitive at late stage. When the damage degree was relatively large, MEP changes at both early and late stages were more sensitive. Conclusions The combined evaluation of GS-MEP can provide an data support for the quantitative evaluation of motor dysfunction after pyramidal tract injury.

国家重点研发计划项目(2016YFC0800702-3),重庆理工大学研究生教育高质量发展行动计划(gzlcx20222091)