围术期应用甲泼尼龙对兔急性脊髓损伤后神经元特异性烯醇化酶表达的影响及意义

目的研究围术期使用甲泼尼龙(MP)对兔急性脊髓损伤后神经元特异性烯醇化酶(NSE)表达的影响及意义。方法将45只家兔随机分为3组,各15只,MP组:暴露脊髓后,用改良Allen's法打击致伤脊髓,随后关闭切口;模型对照组:改良Allen's法进行同等势能打击脊髓后关闭切口;空白对照组:暴露脊髓后,不行脊髓打击,直接关闭切口。术后连续7 d使用青霉素40×104U肌内注射,每日2次,术后饲养4周。于术前1 h,术后12、24、48、72 h分别采血用酶联免疫吸附试验测定血清NSE。术后7、14、28 d分别取3只动物处死,取损伤段脊髓行HE染色光镜下观察脊髓形态改变及神经元改变,免疫组化检测NSE。术后2 h及7、14、28 d分别行改良的Tarlov评分,观察脊髓功能恢复情况。结果①MP组和模型对照组血清NSE在急性脊髓损伤后4 h出现明显增高,12 h达到高峰,48 h降至正常(P<0.05)。②MP组与模型对照组术前1 h、术后2 h、术后2周差异无统计学意义(P>0.05),术后4周MP组Tarlov评分较对照组高,差异有统计学意义(P<0.05)。结论围术期使用MP可降低急性脊髓损伤后兔血清中NSE浓度,减少损伤脊髓神经元中NSE的释放,从而保护神经元,改善神经功能。

Effect of Mthylprednisolone on Neuron Specific Enolase after Acute Spinal Cord Injury during Perioperative Period

Objective To investigate effect of methylprednisolone(MP)on neuron specific enolase(NSE)expression after acute spinal cord injury during perioperative period.Methods 45 rabbits were randomly divided into three groups.Group 1 was made into the incomplete spinal cord injury by the method of advanced Allen′s and treated by methylprednisolone.Group 2 got the same injury,but was treated by normal saline as contrast.Group 3 was performed the operation of total laminoectomy and injected normal saline.Post operation managements included penicillin 400 000 U intramuscularis bis in die in the first 7 d after surgery and artificial feeding 4 weeks.Then group 1 was administered with methylprednisolone protocol(30 mg/kg bolus),the first day 10 mg,next day 8 mg and the third day 5 mg after surgery.The group 2 and 3 were infused with the same volume of saline as contrast.Blood samples were collected in the times as follows:Pre-injury 1 hour,post-injury 4 h,post-injury 12 h,post-injury 24 h,post-injury 48 h,post-injury 72 h.Three rabbits were chosen randomly to check the injured spinal cord and performed wih HE stain,and immunolhistochemical of NSE 7 d,14 d,28 d after surgery.The rabbits were evaluated the motor function as the advanced Tarlov method at the time follows:pre-injury 1 hour,post-injury 2 h,post-injury 7 d,post-injury 14 d,post-injury 28 d.Results ① MP group and the model group serum levels of NSE increased at post-injury 4 h,which reached peak value at 12 h,and back to the normal level at 48 h(P<0.05).②MP group and model control group at 1 h before operation,2 h after operation,2 weeks after operation,the difference was not statistically significant(P>0.05),after 4 weeks in the MP group Tarlov was higher than the control group,the difference was statistically significant(P<0.05).Conclusion Methylprednisolone can decrease the concentration of the serum NSE and inhibit the spinal cord to deliver NSE,which can protect neuron,promote the recovery of neurological function.