大鼠颈神经前支受压后电生理及解剖学改变

Electrophysiological and electron-microscopic changes after compression of ventral branches of cervical nerve in the rats.

目的观察大鼠颈神经前支受压后的电镜及电生理改变,设计大鼠颈神经前支受压模型。方法Wistar雄性大鼠,用直径1 mm硅胶管,纵形切开,于接近背根神经节远端套入颈6神经前支,以丝线在硅胶管外轻松结扎。结扎前、术后2周及4周测定肌皮神经躯体诱发电位,并于2周、4周取受压部位神经段、对侧正常神经及双侧背根神经节作电镜检查。结果受压2周及4周后肌皮神经躯体诱发电位波幅低于结扎前,潜伏期比结扎前延长,差异有统计学意义。受压段神经呈纤维变性、神经脱髓鞘及炎症改变。结论本模型具有切实可行、经济、方便的特点,可作为颈神经受压进一步研究的实验模型。

Objective To investigate the electrophysiological and electron - microscopic changes after compression of ventral branches of cervical nerve in an attempt to design the nerve compression model of ventral branches of cervical nerve in the rats. Methods The ventral branches of the 6th cervical nerve of the rats was clipped by a 5 - mm - long polyethylene catheters （ diameter, I mm） near the dorsal root ganglion, the catheter was cut vertically, bind up the nerve inside, then ligated by silk thread extemally. Evoked potentials of musculocutaneous nerve were measured before and 2 weeks, 4 weeks after nerve compression. The compressed segment, contralateral normal nerve and bilateral dorsal root ganglion were sampled to be observed under electron - microscope. Results As compared with pre - compressive values, 2 weeks and 4 weeks after compression, the amplitude of evoked potentials of musculocutaneous nerve was significantly decreased, the latent period was significantly increased. The compressed segment showed fibrotic, demyelinating and inflammatory changes under the electron - microscope. Conclusion It is a practicable, economic and convenient chronic nerve compression model, and can be used in the study of cervical nerve compression.