腰椎管狭窄动物模型的实验研究

An experimental study of a rat model of lumbar spinal canal stenosis

目的 :建立腰椎管狭窄 (lumbar spinal canal stenosis,L SCS)的动物模型 ,在此基础上进行步态、知觉过敏、电生理及组织学研究。方法 :L SCS组选用 8周的 Wistar大鼠 2 8只 ,切除腰 5腰椎棘突、椎弓 ,并移植碎骨片于此处。Sham手术组为 6只 ,仅切除椎弓。对照组为 3只 ,不作任何处理。术后 8、9个月进行步态、知觉过敏及脊髓体感诱发电位的波幅 (SSEP)的测定 ,同时 ,术后 9个月进行组织学分析。结果 :LSCS组 ,术后 8个月步行距离明显减少 ,步容出现变化 ,Seep的振幅明显减小及知觉出现过敏。术后 9个月步行距离明显减少、步容出现变化、知觉出现过敏及 Seep的振幅明显减小的同时 ,椎管横断面积减少 ,粗纤维减少而细纤维增多。结论 :腰椎管狭窄后 ,大鼠步行分析、电生理学及组织学均出现明显异常。为以后药物治疗的研究打下基础。

Objective:To establish an animal model of lumbar spinal canal stenosis and to study the walking track, paw-withdrawal latencies to thermal stimuli,and electrophysilogical and histological examination.Methods:Twenty-eight 8-week-old Wistar rats were subjected to laminectomy of the fifth lumbar spinal vertebra and bone grafting in lumbar spinal canal stenosis(LSCS). Six 8-week-old Wistar rats were just subjected to laminectomy of the fifth lumbar spinal vertebra in sham operation group. Three 8-week-old Wistar rats were left intact as the control group. 8,9 months later walking track analysis, paw-withdrawal latencies to thermal stimuli, Spinal somatosensory evoked potentials was performed and then the spinal cords were histologically examined. Results:In the LSCS group, walking track distance was significantly shorter than that in the control group 8 or 9 months postoperatively. And the amplitude of SSEPs in the LSCS group was significantly lower than the SSEPs in the control group. Paw-withdrawal latencies was also decreased. In the histological study decrease of large-caliber myelinated fibers and increase in the number of small-caliber myelinated fibers were observed in the LSCS group.Conclusion:We may conclude that in an animal model of lumbar spinal canal stenosis the changes of walking track, paw-withdrawal latencies to thermal stimul electrophysilogical and histological examination appeared.