腰神经根损伤后神经细胞黏附分子在神经肌肉接头部的表达

Expression of neural cell adhesion molecule during regeneration following lumbar nerve root injury in rats

目的 研究大鼠腰神经根损伤后 ,神经细胞黏附分子(N CAM )在神经肌肉接头部的表达。方法 采用免疫组织化学方法和激光共聚焦显微扫描技术 (Confocallaserscaningmicroscopy) ,观察了大鼠胚胎期 ,出生后 14d ,成年期以及L5神经根受压后 10、2 0和 30d ,大鼠比目鱼肌神经肌肉接头部N CAM的分布变化。结果 大鼠胚胎期 ,肌管的表面和神经肌肉接头部N CAM呈强烈着染 ,在发育过程中其浓度逐渐减退 ,至成年肌肉时几乎消失。而当肌肉失神经支配后可导致N CAM重新再现。结论 N CAM在肌肉中的表达是通过神经支配状况调节的。

Objective To study the expression of neural cell adhesion molecule (N CAM) in neuromuscular junctions (NMJ) after L 5 nerve root compressed in rats. Methods Using immunohistochemistry and confocal laser scanning microscopy techniques, the changes of N CAM in NMJ of soleus muscles were observed in embryonic, postnatal and adult rats and 10,20 and 30 days after L5 nerve root was compressed. Results N CAM was present on the surface of myotubes and NMJ in embryonic rats, but it was lost as development proceeded and was nearly absent from adult muscle. However, denervation of adult muscle resulted in the reappearance of N CAM. Conclusion The expression of N CAM in muscle is regulated by the muscles’state of innervation.