缺血前和缺血后联合应用丙泊酚对兔脊髓缺血再灌注损伤的保护作用

Protective effect of combining propofol pretreatment and posttreatment on ischemic spinal cord injury in rabbit

目的探讨缺血前和缺血后联合应用丙泊酚对兔主动脉阻断脊髓缺血性损伤的影响。方法 24只日本大白兔随机双盲均分为三组:假手术组、缺血再灌注组、丙泊酚保护组。缺血再灌注组采取主动脉阻断40min建立脊髓缺血损伤模型,丙泊酚保护组于主动脉阻断前10min及再灌注即刻分别以微量输液泵持续静脉输注丙泊酚(30mg/kg溶于30ml0.9%氯化钠注射液,以3ml/min的速度泵注),另外两组以同样方法静脉泵注等容量0.9%氯化钠溶液作对照。术后行后肢神经功能评分、脊髓组织病理学改变检测、丙二醛(MDA)含量和超氧化物歧化酶(SOD)活性测定。结果与假手术组、丙泊酚保护组比较,缺血再灌注组日本大白兔后肢神经功能评分和脊髓组织病理学有显著改变(P<0.01);缺血再灌注组脊髓中MDA水平显著高于假手术组,丙泊酚保护组脊髓中MDA水平显著低于缺血再灌注组(P<0.01);与假手术组比较,缺血再灌注组脊髓中SOD活性明显减弱(P<0.01),丙泊酚保护组脊髓中SOD活性明显强于缺血再灌注组;假手术组与丙泊酚保护组的所有参数均无统计学差异。结论丙泊酚缺血前和缺血后联合应用对兔脊髓缺血再灌注损伤有良好的保护作用,并可能与其具有较强的抗过氧化反应作用有关。

Objective To study the effect of combined application of propofol preconditioning and postconditioning on spinal cord injury induced by ischemia/reperfusion (I/R) in a rabbit model.Methods The rabbits were randomly assigned to one of the 3 groups(8 rabbits per group):Group I,sham-operation group; Group Ⅱ,ischemic-reperfusion group; Group Ⅲ,ischemic-reperfusion group with propofol treatment.Spinal cord ischemia was induced by infra-renal aortic cross-clamp for 40 minutes in Group Ⅱ and Group Ⅲ,and propofol was intravenously infused at 30 mg/kg in 30 ml 0.9% sodium chloride at the speed of 3 ml/min to animals in Group Ⅲ,once at 10 minutes before aortic clamping and once at the onset of reperfusion.Results Compared with the results in Group Ⅰ,Group Ⅱ showed significant I/R injury-induced changes in the neurological function scores and histopathology (P<0.01).However,Group Ⅲ with propofol treatment significantly reversed these changes in all these parameters (P<0.01).Meanwhile,I/R-induced increase in the malondialdehyde (MDA)content observed in Group Ⅱ were also significantly reduced in Group Ⅲ with propofol treatment (P<0.01),and I/R-induced decreased in the superoxide dismutase (SOD)activities were also significantly prevented in propofol-treated Group Ⅲ (P<0.01).With propofol treatment,all parameters examined in Group Ⅲ were not significant different to those obtained in the sham-operation group.Conclusions Combined application of propofol preconditioning and postconditioning show potently protective effects against spinal cord I/R injury in the rabbit model,and also protect loss of antioxidant activities of the spinal cord tissues.