大鼠脊髓针刺损伤程度与脊髓功能变化的相关性研究

目的通过观察大鼠脊髓穿刺致不同损伤程度后病理生理、运动及电生理改变,寻找对脊髓损伤程度最小的方法,为进一步研究局麻药脊髓毒性提供新的途径。方法健康SD大鼠144只随机分为对照组和实验组,实验组又分为A组(29G)、B组(25G)和C组(21G)。实验动物暴露L4-5节段间硬脊膜,直视下分别用21G、25G、29G刺伤L4-5节段脊髓,缝合切口。各组分别在术前进行双后肢运动功能评分,术后各时点记录运动功能评分(BBB评分)、电生理检测及脊髓病理观察。结果对照组麻醉恢复后能站立行走,脊髓结构正常。实验组29G组行为学评分最高,脊髓损伤区域无明显病理改变;21G组运动、脊髓电生理和组织病理的改变明显,2周时明显恢复。结论应用29G穿刺针对脊髓进行针刺对大鼠脊髓功能影响小,具有穿刺损伤小、重复性好的优点,可为研究局麻药脊髓毒性提供新途径。

Relationship between spinal function and the severity of spinal cord injury by needle puncture

Objective To observe the changes in spinal cord pathophysiology,motor function and electrophysiology after spinal cord injuries induced by punctures with different needles,and explore a new means for studying spinal neurotoxicity of local anesthetics.Methods A total of 144 SD rats were randomly allocated into the sham-operated group(n=36) and 3 spinal cord injury groups(n=36) with the L4-5 segment of the dura mater of the spinal cord punctured using 29G,25G,and 21G needles.The BBB scores before surgery were recorded,and at 8 h,24 h,72 h,1 week,and 2 weeks after the surgery,the motor evoked potential(MEP),spinal cord pathology and the BBB scores were examined.Results In the control group,the rats showed normal BBB score,spinal function and microstructure.Spinal cord puncture with 29G needle did not cause obvious pathologies of the spinal cord,whereas puncture with 21G needle resulted in marked changes in the motor function,electrophysiology and histology of the spinal cord,which showed significant improvements at 2 weeks postoperatively.Conclusion Puncture with a 29G needle causes less injuries and minimal functional changes of the spinal cord,which can serve as a new means for studying spinal neurotoxicity of local anesthetics.