不同神经损伤方式对面瘫后肌纤维亚型病变影响的实验研究

The changes of the muscular fiber phynotype at different condition of nerve injury

目的探讨面瘫时不同神经损伤方式对面部不同类型肌纤维去神经肌萎缩的影响。方法采用组织化学等方法分析在不同神经损伤方式情况下,面部肌肉不同类型肌纤维的病理变化。采用电生理方法检测神经损伤后不同时期肌纤维电刺激收缩阈值和最大收缩力。结果三叉神经支配可以明显减轻Ⅱa、Ⅱb型肌纤维的去神经肌萎缩,肌纤维的电刺激收缩阈值和最大收缩力得以较好维持;而对Ⅰ型肌纤维萎缩的影响不明显。结论临床修复运动神经时应同时对伴发的感觉神经损伤进行修复,这对进一步提高面瘫的临床治疗效果提供了一定的理论指导。

Objective To observe the change of the muscular fiber phynotype at different condition of nerve injury. Methods Rabbits were used as an animal model in this study. The trigeminus and facial nerves of the animal were simultaneously severed （group 1） or only the latter was severed （group 2）. The morphologic change of the muscular fibers was observed with histochemieal methods; the tension of contraction and the threshold value of electrical stimulation were observed with electrical physiological methods. Results Trigeminus nerve play an important role in delaying muscular atrophy after facial nerve was severed. The atrophy degree of type Ⅱa and Ⅱb muscular fibers was less in group 2 than that in group 1. The change of type Ⅰ muscular fibers was not affected by trigeminus nerve. New muscular fibers emerged in group 2. The tension of contraction and the threshold value of electrical stimulation were better in group 2 than that of in group 1. Conclusions Sensory nerve could delay muscle atrophy after denervation. Sensory nerve should be repaired simultaneously when the motor nerve was sutured. The results of this study would facilitate clinical treatment for facial palsy.