预先静脉注射维生素C对兔脊髓缺血再灌注损伤的保护作用

The Protective Effect of Vitamin-C Intravenous Infusion on Rabbits Subjected to Ischemia-reperfusion after Spinal Cord Injury

目的:探讨预先静脉注射维生素C注射液对免脊髓缺血再灌注损伤的作用,并为其临床应用提供依据。方法:30只成年雄性家兔随机分成假手术组(A组)、缺血对照组(B组)、维生素C组(C组)各10只。A组仅松套腹主动脉;B组阻断左肾动脉下腹主动脉40min后再灌注4d,建立脊髓缺血再灌注损伤模型;C组于阻断腹主动脉前15min一次性静脉注射维生素C注射液0.5g/kg,其余操作同B组。于缺血即刻,再灌注即刻、2h、4h、8h、16h测定血清丙二醛(MDA)含量和超氧化物歧化酶(SOD)活性;于再灌注24h、48h和96h采用Tarlov评分评定后肢神经功能;于再灌注96h观察脊髓组织病理学改变。结果:缺血再灌注各时点,家兔血清MDA含量:A组<C组<B组;SOD活性:A组>C组>B组;B组和C组间差异有统计学意义(P<0.05)。于各评定时间点,A组家兔无瘫痪,B组10只均完全性瘫痪,C组仅3只完全性瘫痪,B组和C组间差异有统计学意义(P<0.05)。于再灌注96h与B组比较,C组家兔脊髓前角正常神经细胞数较多,凋亡神经元较少(P<0.05)。结论:预先静脉注射维生素C对免脊髓缺血再灌注损伤有较好的保护作用。

Objective： To investigate the protective effect of vitamin-C Intravenous infusion on rabbits subjected to ischemiaTreperfusion（I-R） injury after spinal cord ischemia. Methods： Thirty rabbits were randomly divided into three groups, A （sham operated,no I R injury）,B （control group,only with I-R injury）,and C（I-R injury plus vitamin-C intravenous infusion）. Spinal cord ischemia was induced by clamping the abdominal aorta below the left renal artery for 40 minutes. The animals in group C have been injected with vitamin-C （0.5g/kg） 15 minutes earlier before clamping the abdominal aorta. The concentration of malonyldialdehyed （MDA） and activities of SOD in serum were measured at different time points after reperfusion. The neurological function was assessed 24,48 and 96 hours after reperfusion according to Tarlov＇s Scale. Spinal cords were harvested for histological analysis. Results;Reperfu- sion after spinal cord ischemia induced the increase of MDA whereas decreased activity of SOD. There were signifi- cant differences in the concentration of MDA and SOD among three groups. The neurological status in the groups C was significantly improved when compared with that of the group B（P^0.05）. In the group B,all animals were pa- raplegic with Tarlov＇s Scale of 0 or 1. Three of 10 animals in the group C were paraplegic with Tarlov＇s Scale of 0 or 1. After vitamin-C intravenous infusion , neuronal death in the spinal cord after ischemic reperfusion was significantly alleviated when compared with the controls （P〈0.05）. Conclusion：Intravenous infusion of vitamin-C can protect the spinal cord against ischemia.