高压氧预处理对大鼠急性脊髓损伤后神经细胞凋亡的影响

Effects of preconditioning with hyperbaric oxygen on neural cell apoptosis after acute spinal cord injury in rats

目的探讨高压氧预处理对急性脊髓损伤后不同时期神经细胞凋亡的影响及神经保护机制。方法将55只SD大鼠随机分为高压氧预处理组(25只)、正常损伤组(25只)及对照组(5只)。大鼠急性脊髓损伤模型制作采用改良Allen's法,分别于伤后1d、5d、7d、10d和14d在脊髓损伤部位取材,应用苏木精-伊红染色、原位缺口末端标记(TUNEL)方法检测大鼠脊髓损伤后的神经细胞凋亡情况。结果预处理组和单纯损伤组均见TUNEL阳性凋亡细胞,而预处理组凋亡细胞数减少;在各时间点预处理组与单纯损伤组差异均有统计学意义(P<0.05)。结论高压氧预处理可减少继发性脊髓损伤细胞凋亡,因而可促进脊髓损伤后修复,对中枢神经系统损伤具有保护作用。

Objective To study the effects of preconditioning with hyperbaric oxygen on neural cell apoptosis at different time periods and the mechanism ofneuroprotection after acute spinal cord injury in rats. Methods Fifty-five adult Spragne-Dawley rats were randomly divided into 3 groups： hyperbaric oxygen preconditioning group （n = 25）, normal injury group （n = 25） and control group （n = 5）. In the experimental groups, the spinal cord injury models were established by Allen＇s method. The samples were taken from the spinal cord injury sites at days 1, 5, 7, 10, 14 after the injury and tested by hematoxylin and eosin staining for morphology and by TUNEL method for cell apoptosis. Results The apoptotic cells positive of TUNEL were detectable in both two experimental groups. In the preconditioning group, the number of apoptotic cells was less and neuronal function of the spinal cord better as compared with those in the control group. There were statistically significant differences between the preconditioning group and normal injury group especially the control group （P 〈 0.05）. Conclusion The hyperbaric oxygen preconditioning can reduce the number of apoptotic cells and promote the nerve function recovery in rats after spinal cord injury.