大鼠脊髓缺血再灌注后血清内皮抑素变化及其与脊髓损伤的关系

Variation of serum endostatin and its relationshipwith spinal cord is chemia-reperfusioninjury in rats

目的观察大鼠脊髓缺血再灌注后血清内皮抑素(SE)水平变化及其与脊髓损伤的关系.方法采用Naslund腹主动脉阻断法制作脊髓缺血再灌注模型.将56只大鼠分为假手术对照组(C组,n=8)和模型组(M组,n=48).C组只解剖出腹主动脉但不阻断;M组按腹主动脉阻断时间分为M1组(n=24)和M2组(n=24),分别阻断30min和90min.各组均于再灌注后6～8h、2d、7d取血样和脊髓标本,分别进行SE检测(ELISA法)和脊髓组织学检查.结果①脊髓病理检查:M1组脊髓病理改变较轻,再灌注后7d可恢复正常;M2组运动神经元损伤较重,多数呈不可逆性坏死表现.②SE水平:C组为(56±10)ng/ml;M1组无显著变化;M2组于再灌注后2d开始升高达(85±17)ng/ml,与C相比P=0.01;7d时达(92±16)ng/ml,与C相比P<0.01.结论脊髓缺血90min导致不可逆性脊髓损伤,SE水平亦显著升高.

Objective：To investigate the variations of the serum endostatin level （SE）and its relationship with spinal cord injury in the rats suffered from spinal ischemia-reperfusion lesions. Methods：The spinal ischemiareperfusion lesions models were created by using of Naslund abdominal aorta occlusion. 56 rats were divided into control group （C,n=8）and model group （M,n=48）. Group C were only performed the abdominal aortic anatomy with no occlusion followed. Abdominal aorta of group M were occluded for 30 minutes （group Ml,n=24）and 90 minutes （group M2,n = 24）. Samples of blood and spinal cord were delivered 6～8 hours, 2 days,and 7 days respectively after operation. Variations of serum levels of endostatin were evaluated using competitive enzyme linked immunosorbent assay （ELISA）. Histological changes of spinal cord biopsy were examined. Results：①Spinal cord morphological examinations：Tissue edema in group M1 were slight and recovered on the 7th day. But in the group M2 the morphological changes of motor neurons were severe （many of the subjects suffered irreversible necrosis）.②Serum endostatin ：The mean level of SE in group C was （56±10）ng/ml. There was no significant change between group M1 and group C. For group M2,SE level increase to （85±17）ng/ml 2 days after reperfusion,and reached （92±16）ng/ml on the 7th day,which significantly higher than that in group C. Conclusion：90 minutes ischemia can render the rats＇ spinal cord into irreversible lesions. Meanwhile the serum endostatin level increases markedly.