目的探讨头颅侧向旋转致脑损伤大鼠模型脑干听觉诱发电位(BAEP)的变化及机制。方法成年大鼠20只,制作头颅瞬间侧向旋转脑损伤模型,测量头颅旋转前及旋转后6h的BAEP,测量电极置于颅顶左侧c2点,左耳予短暂click声刺激,右耳持续予噪声掩蔽,经1000次叠加平均,记录BAEP各波形的潜伏期、波间期和波幅值。结果大鼠头颅旋转后6h和Ⅴ波潜伏期、Ⅰ~Ⅲ和Ⅲ~Ⅴ波波间期明显较旋转前延长,Ⅰ和Ⅴ波波幅较旋转前明显降低,而旋转前后Ⅰ波潜伏期、Ⅰ~Ⅴ波波间期以及Ⅰ波波幅无显著差异。结论头颅瞬间侧向旋转可引起BAEP异常,此与脑干内特殊传导通路的破坏有关,其结构基础为脑干广泛神经轴索损伤。
Objective To study the change and mechanism of brainstem-auditory evoked potential (BAEP) in rat model with brain injury by lateral head rotation. Methods The model of brain injury by lateral head rotation was produced with 20 adult rats. The rats'BAEP was measured before rotation and at 6 h after rotation. The test electrode was placed at the left C2 on the head. The short click sound was given to the left ear and continual sheltering was sent to the right ear. One thousand test results were added and then averaged. The latent period, wave-to-wave interval and amplitude of all waves in BAEP were recorded. Results Compared with the BAEP before head rotation, the latent period of wave Ⅰ ,Ⅴ and the wave-to- wave interval of Ⅰ -Ⅲ, Ⅲ-Ⅴ V were apparently prolonged, and the amplitude of wave Ⅲ, V was markedly reduced at 6 h after rotation ; on the other hand, no significant difference was found in the latent period of wave Ⅰ , wave-to-wave interval of Ⅰ, Ⅴ and amplitude of wave Ⅰ . Conclusion Lateral head rotation leads to abnormal BAEP. It is related to the damage of special conductive pathways in brainstem. The diffusely-scattered axonal injury in brainstem is the pathological basis in this animal model by mechanic head rotation.