低温联合腺苷预处理对脊髓缺血再灌注损伤后炎症因子的影响

Protective effect of adenosine at hypothermia on inflammatory factors after spinal cord ischemiareperfusion injury

目的观察腺苷联合深低温对大鼠脊髓缺血再灌注的保护作用及对炎症因子表达的影响,初步探讨其可能的作用机制。方法将54只Sprague Dawley大鼠按电脑随机数字表法随机分为3组:常温37℃手术对照组(缺血再灌注组,n=18);低温18℃处理组(H组,n=18);腺苷+低温18℃处理组(AH组,n=18),腹主动脉夹闭前10 min尾静脉注射腺苷,用量为0.06 m L/100 g,浓度为5 mg/m L。于缺血再灌注6、12、24 h,各取6只进行行为学评分,分别取L2-L5节段脊髓组织,同时取心腔血2 m L于干燥管中,2 000 r/min离心10 min,取血清-20℃保存待测。动态测定脊髓组织及血浆中白细胞介素(interleukin,IL)-1β、IL-8浓度的变化。结果 3组行为学评分早期均有下降,随时间推移评分逐渐升高,缺血再灌注组各时间段评分均低于H及AH组,且AH组评分高于H组,差异有统计学意义(P<0.01)。Western blot法检测结果显示,H及AH组脊髓组织中IL-1β、IL-8比缺血再灌注组表达减少,且AH组低于H组,差异有统计学意义(P<0.05)。ELISA检测结果显示,缺血再灌注组血浆中IL-1β、IL-8表达明显高于H及AH组,AH组低于H组,差异有统计学意义(P<0.05)。结论腺苷联合深低温对大鼠脊髓缺血再灌注有保护作用,且保护效果优于单独运用低温处理,其可能机制是通过抑制炎症因子的表达而发挥保护作用。

Objectives To evaluate the changes in expression of interleukin（IL）-1β and IL-8 after spinal cord ischemiareperfusion injury（SCII） and after exposing to deep hypothermia with adenosine preconditioning in rats. Methods Totally54 Sprague Dawley rats were randomly divided into 3 groups ： spinal cord ischemia-reperfusion injury（I / R） group（n =18）; 18℃ administration group（H group）（n=18）; 18℃ with adenosine administration group（AH group）（n=18）,and in this group lll the rats were given experimental SCII,exposed to deep hypothermia and injected adenosine（0.06 m L / 100 g,density ： 5 mg / m L） through the caudal veins. Spinal cord was assessed by the Modified Tarlov Scale at 6 h,12 h,24 h after reperfusion. Expressions of IL-1β and IL-8 in spinal cord tissues and blood were detected by Western blot analysis and enzyme-linked immunosorbent assay（ELISA）. Results Spinal cord scores in the three groups decreased at the beginning,while gradually increased in course of time. The spinal cord score in I / R group was much lower than those in H group and AH group,and the score in AH group was significantly higher than that in H group（P〈0.01）. Western blot analysis showed that IL-1β and IL-8 expressions in spinal cord tissues increased in all the groups and the levels in AH group and H group were lower than those in I / R group. IL-1β and IL-8 expressions in H group were significantly higher than those in AH group（P〈0.05）. ELISA showed that IL-1β and IL-8 expressions in blood increased in all the groups and the levels in AH and H groups were significantly lower than those in I / R group. IL-1β and IL-8 expressions in H group were significantly higher than those in AH group（P〈0.05）. Conclusions Deep hypothermia with adenosine can protect the spinal cord from ischemia-reperfusion injury by inhibiting IL-1β and IL-8 expressions.