大鼠脊髓压迫性损伤后脱髓鞘病变及硫酸软骨素蛋白多糖的表达变化  

- Demyelination and changes in chondrotin sulfate proteoglycan expression after spinal cord compression injury

作　　者：黄思琴[1] 漆伟 孙善全 汪克建 蒋锦 陆蔚天 

机构地区：[1]重庆医科大学中医药学院针灸推拿教研室,重庆400016 [2]基础医学院解剖教研室

出　　处：《中华物理医学与康复杂志》2013年第4期245-249,共5页Chinese Journal of Physical Medicine and Rehabilitation

基　　金：国家自然科学基金（30270437）;重庆市卫生局中医药科技项目（2012-2-138）;重庆市教委科学技术研究项目（KJ120312）

摘　　要：目的探讨脊髓压迫性损伤（CSCI）后脱髓鞘病变及硫酸软骨素蛋白多糖（CSPG，NG2）的表达变化。方法选取健康成年SD大鼠75只，雌雄不限，采用随机数字表法将其分为正常组、假手术组、CSCI1d组、CSCI3d组和CSCI7d组，每组15只。采用自行设计的大鼠脊髓压迫器制作脊髓压迫模型，应用BBB运动功能评分、锇酸染色及透射电镜观察CSCI后1d、3d及7d时大鼠的运动功能情况及白质有髓神经纤维的病理变化，计算脊髓后索有髓神经纤维的数量及髓鞘厚度与轴突直径的比值即G-ratio值，并采用免疫印迹法检测NG2蛋白的表达变化。结果CSCI后，CSCI1d组、CSCI3d组和CSCI7d组的大鼠后肢BBB评分分别为（1．23±0．45）分、（0．654±0．35）分和（0．00±0．00）分，与正常组（21．004±0．00）分和假手术组（21．00±0．00）分相比，差异有统计学意义（P〈0．05），大鼠的运动功能随受压时间延长而逐渐下降。锇酸染色显示正常组和假手术组大鼠的白质正常，脊髓受压后，CSCI1d组、CSCI3d组和CSCI7d组的有髓神经纤维开始出现水肿、变性、崩解，正常组和假手术组脊髓后索的有髓神经纤维计数分别为（2771±108）根和（2675±199）根，CSCI1d组、CSCI3d组和CSCI7d组的有髓神经纤维计数分别为（2403±161）根、（1708±70）根和（8104-95）根，压迫后有髓神经纤维数目减少，压迫后7d，有髓神经纤维数目减至最低（P〈0．05），与正常组和假手术组比较，差异有统计学意义（P〈0．05）。电镜定量分析结果显示，正常组、假手术组、CSCI1d组、CSCI3d组和CSCI7d组的G—ratio值分别为（18．104±0．4）、（17．704±1．0）、（6．694±0．8）、（5．73±0．4）和（4．954±0．5），CSCI1d组、CSCI3d组和CSCI7d组的G—ratio值均较正常组和假手术组低，且在压迫后7d时降至最低，差异有统计学意义（P〈0．05）。透射电镜结果Objective To investigate the role of demyelination and the alteration of chondrotin sulfate proteoglyean （CSPG,NG2） expression after compression injury of the spinal cord （CSCI）. Methods Seventy-five adult Sprague-Dawley rats were randomly divided into a normal group, a sham-operation group, a CSCI 1 day group, a CSCI 3 day group, and a CSCI 7 day group. There were 15 rats in each group. The injuries in the CSCI groups were inflicted using a technique devised in our laboratory. Basso-Beattie-Bresnahan （BBB） neurological function assess- ment was used to assess the rats＇ motor function, osmic acid staining and transmission electronic microscopy （TEM） were used to observe any pathological changes of myelinated nerve fibers in the white matter at 1, 3 and 7 days after CSCI. The amount of myelinated nerve fibers in the posterior funiculus of the spinal cord and the ratio of myelin sheath thickness to axon diameter （the G-ratio） were calculated. Any alteration in NG2 expression was observed by Western blotting. Results The average neurological function assessment scores in the CSCI groups were （1.23 ± 0.45 ） , （0.65 ± 0.35 ） and （0.00 ± 0.00） respectively. Compared with the normal group （21.00 ± 0.00） and the sham operation group （21.00 ± 0.00 ） , the differences were all statistically significant. The rats＇ motor function deteriorated gradually with time after the CSCI. Osmic acid staining showed that the white matter was intact in the normal and sham groups. After being compressed the myelinated nerve fibers became swollen, degenerated and broke down. The amount of myelinated nerve fibers in the normal group, the sham operation group and the three CSCI groups was （2771 ± 108） , （2675 ± 199）, （2403 ± 161 ） , （ 1708 ±70） and （810 ±95） respectively. The amount of myelinated nerve fibers decreased in the CSCI groups and reached a minimum on the 7th day. The difference was statistically significant. The TEM quantity analysis showed that the G-ratio

关 键 词：脊髓压迫性损伤 脱髓鞘病变 硫酸软骨素蛋白多糖 

分 类 号：R651.2[医药卫生—外科学]