自制脊髓打击器致大鼠脊髓损伤的组织形态学演变特征

Morphologic characteristics of spinal cord injury in rats caused by self-made spinal cord impactor

目的:通过大鼠脊髓组织H-E染色和电镜观察,以评价自制撞击型脊髓打击器的应用价值.方法:采用自制脊髓打击器分别从2、3 cm和4 cm高度将10 g撞击头自由下落对脊髓进行撞击,以制备大鼠脊髓损伤模型,于制模术后3、7、14d及28 d随机选取各组大鼠样品,对其脊髓组织进行H-E染色及电镜观察.结果:假手术组各观察时间点脊髓组织结构均完整;2 cm高度打击组脊髓损伤后至第7天组织坏死明显,14d后受损组织部分修复;3 cm和4 cm高度打击组随时间延长受损脊髓组织坏死加重.电镜观察3个打击组随时间延长,髓鞘板层均表现为逐渐松解,轴突逐渐消失,尤以3crm和4cm高度打击组的损害更为严重.结论:本研究采用的自制脊髓打击器具有随打击高度的不同而出现不同程度组织损伤的演变特征,是一种较为理想的脊髓损伤制模装置.

Objective:To evaluate the applicable value of self-made spinal cord impactor through observing the injuried spinal cord structure with H-E staining and electron microscopy in rats caused by the device.Methods:Adult SD rats were operated with laminectomy from T9-T11 and the spinal cords were hit by a 10-gram weight impactor hand-free falling at the height of 2,3 cm and 4 cm respectively.Animals in each group were randomly selected at 3,7,14 d and 28 d after surgery and/or spinal cord injury to observe.Their damaged spinal cord tissues were observed by H-E staining and electron microscopy.Results:The spinal cord tissue of rats in sham group showed structural integrity at each time point.Spinal cord tissue of rats in 2 cm-impactor group showed significant necrosis at 7 d and partial repair at 14 d.Spinal cord tissues in the 3 and 4 cm-impact group showed increased damage time-dependently.As for rats in all 3 experimental groups,their myelin lamellae became gradually loose and the axons gradually disappeared under the electron microscope with time.The damages were more serious in the 3 and 4-cm groups.Conclusion:This self-made spinal cord impactor produces different degrees of morphological changes in the spinal cord along with different impact distance.It can be used as an experimental device to make models for spinal cord injury studies.