大鼠脊髓损伤后挫伤部位的X线照射治疗对运动功能恢复的作用研究

X-irradiation of contusion site in rats with spinal cord injury improves the recovery of locomotor function

目的 探讨脊髓挫伤部位的X线照射治疗对脊髓损伤后运动功能恢复的作用.方法 将70只雌性Wistar大鼠按照纽约大学的重力冲击方法建立大鼠脊髓（T10）损伤动物模型,按照随机数字表法分为7组,每组10只,其中6组大鼠在损伤后不同时间（损伤后20 min、1 d、2 d、4 d、7 d、17 d）对挫伤部位进行X线（20 Gy）照射,第7组则不予照射（对照组）.然后根据Basso、Beattie、Bresnahan（BBB）评分标准评测各组大鼠运动功能恢复情况,并进行统计学比较.采用快蓝染色对存活6周以上的大鼠进行挫伤脊髓的组织形态学观察.结果脊髓挫伤后20 min、1 d、2 d行X线照射组BBB评分明显高于对照组,差异均有统计学意义（P〈0.05）,且在脊髓损伤后的2～3周进展较快,后期恢复缓慢.组织形态学观察可见应用X线治疗组周边组织残存区面积大于对照组.结论 脊髓挫伤部位伤后早期行X线照射治疗可保护脊髓残存的神经组织,改善运动功能的恢复.

Objective To determine whether the X-irradiation of the contusion site can improve the recovery of locomotor function following spinal cord injury in rats. Methods The spinal cords of 70 male Wistar rats at the level of T10 were contused with a weight-drop apparatus similar to the NYU impactor. Ten rats were chosen as control group. The other 60 rats were equally randomized into 6 groups and localized X-irradiation （20 Gy） of the contusion site was performed on rats in these 6 group 20 min, 1, 2, 4, 7 and 17 d after the injury, respectively. Locomotor function was determined by the Basso, Beattie and Bresnahan Locomotor Rating Scale （BBB）. Following 6 w of behavioral evaluation, the spinal cords were received histological examination. Results X-irradiation of the contusion site 20 min, 1 and 2 d after the injury significantly improved the recovery of locomotor function as compared with no X-irradiation （control group, P〈0.05）; and the improvement in the 2nd and 3rd w were the quickest among all the time points. Increased amount of spared spinal cord tissue in the X-irradiation groups was found as compared with that in the control group. Conclusion X-irradiation of the contusion site following contusion at an early stage can protect the spared spinal cord tissue and help the recovery of locomotor function.