摘要目的 研究大鼠单侧骶丛撕脱伤后脊髓前角运动细胞元的退变规律.方法 选用体重200 ～ 250 g成年SD大鼠60只,建立单侧骶丛撕脱伤模型,分别于损伤后2,4,6,8,10,12周取大鼠脊髓L4～6节段切片,行HE染色检测脊髓前角运动神经元的存活率;TUNNEL染色检测脊髓前角运动神经元的凋亡指数.结果 撕脱后运动神经元的存活率:2周(92.1±4.7)％,4周(83.6±3.7)％,6周(43.6±4.2)％,8周(32.1±3.5)％,10周(18.4±3.7)％,12周(12.1±3.3)％.损伤侧脊髓前角运动神经元存活率随着损伤时间延长逐渐降低;而凋亡指数随着损伤时间延长逐渐升高,6周时升高比较明显.结论 大鼠骶丛撕脱损伤术后6周可作为脊髓前角运动神经元变化的时间节点,神经修复术宜在此前完成.

abstractsObjective To evaluate the degenerative regularity of motoneurons in anterior horn of spinal cord after unilateral sacral plexus avulsion in rats.Methods Sixty adult SD rats weighing 200-300 g were chosen to establish models of unilateral sacral plexus avulsion.Spinal cord segments of L4-6were removed and sectioned at postinjury 2,4,6,8,10,12 weeks respectively to detect survival rate of motoneurons in anterior horn of spinal cord using HE staining and to detect their apoptotic index using TUNNEL staining.Results Survival rates of motoneurons at weeks 2,4,6,8,10,12 after avulsion were (92.1 ±4.7)％,(83.6 ±3.7)％,(43.6 ±4.2)％,(32.1 ±3.5)％,(18.4 ±3.7)％,and (12.1 ± 3.3) ％,respectively.Consequently,survival rate of motoneurons in anterior horn of spinal cord was decreased gradually as the expansion of injury time,but their apoptotic index presented a gradual increase with time,especially at 6 weeks after injury.Conclusion Six weeks after sacral plexus avulsion in rats may be taken as the time node of changes of motoneurons in anterior horn of spinal cord and nerve repair should be completed in advance of the time node.