中文摘要：

目的：探讨雌激素对兔脊髓缺血再灌注损伤的神经保护效应。方法成年新西兰大白兔肾下腹主动脉钳夹20min恢复再灌注。实验分组如下：Control组（n=8）仅行肾下腹主动脉钳夹20min恢复再灌注；Sham组（n=8）行对照组操作除外肾下腹主动脉钳夹；雌激素处理组（n=8）分别在再灌注开始即刻经兔耳缘静脉给予雌激素200，400，800μg/kg。再灌注后48h进行下肢神经功能评分（Tarlov法）后处死受试动物，取脊髓行组织HE染色切片病理分析。结果Tarlov评分发现雌激素处理组神经功能评分明显高于control组（P＜0.05）。组织病理分析可见脊髓前角运动神经元凋亡，坏死较明显。雌激素处理组脊髓前角运动神经元计数明显多于Control组（P＜0.01）。结论兔脊髓缺血后静脉给予雌激素可明显改善下肢神经功能，增加脊髓前角正常运动神经元数量，减轻缺血再灌注损伤。

英文摘要：

Objective To investigate the neuro-protective role of estrogen in rabbits after occlusion against ischemia-reperfusion （I/R） injury. Methods Occlusion of the abdominal aorta was applied to adult rabbits,followed by removal of aortic clamp and reperfusion. The abdominal aortas of New Zealand White albino rabbits were occluded for 20 min. Experimental groups were as follows： Animals （n=8） in a sham group underwent the surgical procedure but the aorta was not occluded.In Control group,animals （n=8） were subjected to spinal cord ischemia but received no pharmacologic intervention,and estrogen-treated group （n=8） each group）received respectionly 200,400,800μg/kg estrogen intravenously immediately after the onset of reperfusion.Neurological status was assessed at 48h after the operation.Every animal was killed at 48 hour after the procedure. Spinal cords were harvested for histopathologic analyses. Results According to Tarlov＇s scale, neurological status of the rabbits at postoperative 48 hour was better in the estrogen-treated group compared to the I/R group.Histopathologic analyses demonstrated typical morphological changes characteristic of necrosis seriously in control group（P〈0.01）, There were more normal motor neurons at anterior horn of the spinal cord in estrogen groups than those in control group （P 〈 0.01）. Conclusion The effects of estrogen administered after occlusion may significantly reduce the incidence of spinal cord injury following temporary aortic occlusion.