摘要
目的 探讨脊髓损伤大鼠远端运动神经元继发性损害的变化特点.方法 成年雌性SD大鼠40只,采用改良Allen＇s撞击法制作T10不完全性脊髓损伤模型.分别在损伤前、损伤后第1周、2周、3周、4周、5周时采用斜板试验、改良Tarlov评分、BBB评分进行运动功能评定;在各时间点取5只大鼠用4%多聚甲醛心脏灌注,取损伤局部T10节段及损伤远端L5节段脊髓进行形态学检测.损伤前时间点检测结果作为正常对照.结果 ①损伤远端运动神经元病理变化：损伤后第1周时,损伤远端前角运动神经元突起和尼氏体有所减少,胞核和核仁无明显改变;损伤后第2周时,损伤远端前角运动神经元突起和尼氏体进一步减少,核仁模糊、偏位;损伤后第3周时,损伤远端前角运动神经元突起和尼氏体较前无进一步减少,组织内可见萎缩及凋亡神经元;损伤后第4周时,损伤远端前角运动神经元突起和尼氏体较第3周时有所增加,仍可见少数凋亡神经元存留;损伤后第5周时,损伤远端前角运动神经元突起和尼氏体较前明显增多.②损伤局部病理变化：损伤后第1周时,损伤局部灰、白质界限不清,可见出血、炎症反应,灰质部分神经纤维及组织坏死、液化,白质空泡化;损伤后第2周时,损伤局部出血、血肿及炎症反应减退,可见胶质细胞、神经纤维增生和血管新生;损伤后第3周时,损伤局部胶质细胞增生显著,神经纤维增生较多;损伤后第4周、第5周时,损伤局部胶质细胞、神经纤维较前无明显增生.③运动功能变化：损伤后第1周、2周、3周、4周、5周时的斜板角度、改良Tarlov评分、BBB评分均较损伤前显著降低（P＜0.05）;损伤后第2周、3周、4周、5周时各项评分均较第1周时显著增加（P＜0.05）;损伤后第3周、4周、5周时呈增加趋势,但与第2周时比较差异无统计学意义（P＞0.05）.结论 脊髓损伤后早期远端脊髓运动神经元即会发生继发性损害,包括突起和尼氏体减少、细胞萎缩与凋亡,并且与损伤局部病理变化及损伤时程相关.
Objective To explore the changes in secondary lesions to motor neurons caudal to a damage site on the spinal cord of rats. Methods Forty female adult Sprague-Dawley rats were given incomplete spinal cord injuries （SCIs） at the T10 level using a modification of Allen＇s method. Locomotor function was evaluated using an inclined plane test, modified Tarlov scores and the Basso-Beattie-Bresnahan （BBB） scale before the operation and 1,2, 3,4 and 5 weeks post surgery. Histomorphological changes at T10 and L5 were observed under a light microscope.Results ①Morphology of the distal spinal cord： 1 week after SCI, neurites and Nissl bodies of the motor neurons had decreased. By the 2nd week the decrease had become more obvious. At the 3rd week after SCI, neurites and Nissl bodies had not decreased further, but neuron atrophy and apoptosis were found. At the 4th to the 5th week after SCI, neurites and Nissl bodies had increased significantly. ②Morphology of the damage site： At the 1 st week after SCI, hemorrhage and inflammation as well as nerve fiber necrosis were observed. By the 2nd week astrocytes had-increased and a few nerve fibers had grown at the damage site. At the 3rd week, regeneration of nerve fibers and astrocytes were found. At the 4th to the 5th week after SCI astrocytes and nerve fibers had not increased further. ③Locomotion function： The angles of the inclined plane test, Tarlov scores and BBB scores had decreased significantly at the 1st, 2nd, 3rd, 4th and 5th week post injury compared with those before the SCI. The values at the 2nd, 3rd, 4th and 5th week were all significantly better than those at the 1st week after SCI. There was an increasing trend in scores from the 3rd week to the 5th week, but without significant differences compared with the 2nd week after the operation. Conclusions Secondary degeneration and damage, including decreases in neurites and Nissl bodies, neuron atrophy and apoptosis may occur in the motor neurons distal to the damage site in the early stage after SCI. This correlates with changes in the pathology of local damage.
出处
《中华物理医学与康复杂志》
CAS
CSCD
北大核心
2010年第10期721-724,共4页
Chinese Journal of Physical Medicine and Rehabilitation
基金
江苏省兴卫工程重点人才项目（[2007]200）
关键词
脊髓损伤
运动神经元
继发性损害
Spinal cord injury
Motor neurons
Secondary lesions
