糖尿病大鼠运动神经纤维损害的MUNE检测  

The detection of motor nerve injury by MUNE in an animal model of diabetes

作　　者：田丽[1] 程焱[1] 张哲成[2] 刘娜[2] 朱炬[2] 

机构地区：[1]天津医科大学总医院神经内科,300052 [2]天津市第三中心医院神经内科

出　　处：《天津医药》2015年第12期1390-1393,共4页Tianjin Medical Journal

基　　金：天津市卫生局科技基金资助项目(2012KY04);天津市卫生行业重点攻关项目(14KJ110)

摘　　要：目的通过运动单位数目估计(MUNE)技术对糖尿病大鼠运动神经纤维功能状况进行评价,探讨MUNE对糖尿病周围神经病(DPN)的早期诊断价值。方法链脲佐菌素诱导糖尿病大鼠模型(DM组),在造模后第4、8、12周对DM组及对照组(正常SD大鼠)进行腓肠肌MUNE及坐骨神经常规运动神经传导速度(MCV)及波幅(CMAP)检测,电镜观察坐骨神经的超微结构。结果造模后第4周,DM组腓肠肌MUNE低于对照组(275.88±87.87 vs369.71±75.64,P<0.05),而坐骨神经MCV及CMAP较对照组差异无统计学意义;电镜观察显示DM组坐骨神经大部分神经纤维尚正常,少量轴索萎缩,神经髓鞘板层分离。第8周,与对照组相比,DM组腓肠肌MUNE降低(357.49±72.68 vs221.26±92.41,P<0.01),而MCV、CMAP仍较对照组差异无统计学意义;电镜观察显示尚有较正常神经纤维,髓鞘局灶性板层松散、分离,轴索萎缩,轴索膜与髓鞘内层分离,出现大的间隙。第12周,DM组腓肠肌MUNE(127.87±19.80 vs 366.85±51.25)、坐骨神经MCV[(35.06±4.33)m/s vs(50.47±6.07)m/s]、CMAP[(2.91±1.37)mV vs(5.98±2.14)mV]低于对照组(P<0.01);电镜显示神经髓鞘折曲,轴索受挤压等受损严重。结论 MUNE较常规运动神经传导检测易于早期发现DPN轴索功能异常。Objective To investigate motor nerve function status in rats with diabetes mellitus by motor unit number estimation （MUNE）, and discuss it′s early diagnostic value in diabetic peripheral neuropathy （DPN）. Methods Diabetic rat model （DM group） was induced by streptozotocin. The MUNE of gastrocnemius muscle and motor nerve conduction （MCV, CMAP） of the sciatic nerve were measured at the 4th, 8th and 12th week after onset of hyperglycemia in the DM group and the control group （normal SD rats）. The ultrastructure of sciatic nerve was observed by electron microscope. Results At the 4th week, MUNE of gastrocnemius muscle was significantly decreased in DM group compared to that of the control group （275.88 ± 87.87 vs 369.71 ± 75.64,P〈0.05）. There were no significant differences in MCV and CMAP of sciatic nerve between two groups. The electron microscopy observation showed that most nerve fibers were normal;a small amount of axonal atrophy, and myelin lamellar structure was separated in DM group. At the 8th week, compared with the control group, MUNE were reduced in gastrocnemius muscle in DM group （357.49±72.68 vs 221.26±92.41, P〈0.01）. There were no significant differences in MCV and CMAP of the sciatic nerve between DM group and control group. The electron microscope observation showed that part of nerve fibers were normal, the myelin focal plate layer was loose and separated, axonal atrophy, the axonal membrane and myelin sheath inner layer was separated with big gap. At the 12th week, MUNE of gastrocnemius muscle （127.87±19.80 vs 366.85±51.25）, sciatic nerve MCV [（35.06±4.43） m/s vs （50.47±6.07） m/s] and CMAP [（2.91±1.37） mV vs （5.98±2.14） mV] were significantly decreased in DM group than those of control group （P〈0.01）. The electron microscopy observation showed severely damaged myelin flex and axonal squeeze. Conclusion MUNE is much earlier in detecting early motor nerve dysfunction in DM than conventional motor nerve conduction test.

关 键 词：糖尿病神经病变 运动神经元 神经传导 坐骨神经 显微镜检查 电子 透射 运动单位数目估计 

分 类 号：R741.044[医药卫生—神经病学与精神病学]