抑肽酶预处理对家兔脊髓缺血再灌注损伤早期脊髓神经功能及病理学的改善

The effect of spinal cord pathophysiology and neuromotor function during aprotinin pretreated early spinal cord ischemia-reperfusion injury in rabbits

目的观察抑肽酶预处理对兔脊髓缺血再灌注损伤后早期脊髓神经功能及病理学的影响,为临床应用抑肽酶治疗脊髓缺血再灌注损伤提供实验依据。方法国产大耳白兔21只,随机分为实验组(8只)、对照组(8只)和假手术组(5只)。实验组,缺血60min,再灌注24h,于缺血前10min静脉注射抑肽酶30000kIU/kg,继而用Graseby3500微量泵持续注入抑肽酶10000kIU(/kg.h)直至实验结束。对照组,缺血及再灌注时间、方法同实验组,唯一不同的是对照组用生理盐水代替实验组的抑肽酶。空白组,只暴露腹主动脉,不夹闭,不给药。缺血前、再灌注8h、24h耳缘动脉抽取动脉血3ml形MDA及SOD检查,4h、8h、12h及24h行后肢运动功能评分。再灌注24h处死动物,取动物腰段脊髓(L3-L4)进行病理学处理,光镜、电镜下观察脊髓前角运动神经元数量及形态变化。结果再灌注后8h、24h,实验组MDA含量明显减少,而SOD活力增加(P<0.05)。12h、24h,后肢运动功能改善(P<0.05)。病理学观察,脊髓前角运动神经元计数实验组较对照组增高(P<0.05),细胞凋亡减少,形态正常。结论抑肽酶预处理可以明显降低缺血再灌注后脊髓组织中MDA含量、提高SOD活力、改善后肢运动功能,减少再灌注后细胞的坏死和凋亡,保护神经组织的功能。

Objective To observe The effect of spinal cord pathyophysiology and neuromotor function during aprotinin pretreated early spinal cord ischemia-reperfusion injury in rabbits,and provide substructural experimental theory. Methods twenty-one rabbits were randomly divided into aprotinin treatment group （8 rabbits）and normal saline control group （Srabbits） and sham-surgical operation group （5 rabbirs）. The infrarenal segment in abdominal aorta was clamped for 60 minutes to construct the model of lumbosacral spinal cord ischemia in rabbits. Reperfusion was followed and kept on for twenty-four hours until the blood flow regained normal. Aprotinin was given 3×107 IU/ kg as a short time intravenous injection for 10 minutes before ischemia,and then was drilled with micro pump by 1×107IU/kg /（kg·h）. Normal saline was used in control group,the ischemia-reperfusion duration between aprotinin treatment group and normal saline group remained same. Sham-surgical operation group were only exposured abdominal aorta and were not clamped. 3ml bloods drawn from the rabbits＇ ear fringe artery were used to examine the content of malonaldehyde and the activity of superoxide dismutase before ischemia and at 8 hour,24 hour after ischemia-reperfusion. At 4h,8h,12h and 24h after ischemia-reperfusion,to evaluate the posterior limb neuromotor function. The lumbar segments （L3-L4）were harvested to complete analysis of histopathology. Results At 8h,24h after spinal cord ischemia-reperfusion,eompared with the control group,the content of malonaldehyde were less,however,the activity of superoxide dismutase was more in the experimental group （P〈0.05）. At 12hand 24h the posterior limp motor function was improved （P〈0.05）. Neurons morphous were normal;apoptosis was less in experiment group. Conclusion Aprotinin pretreatment can reduce the content of malonaldehyde and ascend the activity of superoxide dismutase and improve posterior limb motor function and apoptosis of nerve cell.