腰椎间盘突出症大鼠模型的建立及病理动态研究

Study on the Establishment of a Rat Model of Lumbar Disc Herniation and Its Pathological Dynamics

目的建立腰椎间盘突出症(lumbar disc herniation,LDH)大鼠模型,对建模后不同时间点模型效果进行动态比较以期发现建模后的最佳实验节点。方法将48只Sprague-Dawley(SD)大鼠随机分为对照组(假手术组)、模型组,采用大鼠自体髓核移植法建立LDH大鼠模型。造模术后于不同时间节点(第7、14、21、28天)观察动物行为状态并随机处死动物后进行血清学和病理组织学检查。通过HE染色观察大鼠神经组织病理学的改变,采用ELISA法检测血清肿瘤坏死因子-α(tumor necrosis factor-α,TNF-α)水平。结果(1)造模术后模型组和对照组(假手术组)大鼠均有明显的左后肢无力、跛行症状。术后第7天开始,对照组症状有恢复的趋势,并于第14天后基本恢复正常;模型组症状持续存在至术后第28天有好转趋势。(2)术后第7天对照组(假手术组)神经组织可见出血及炎症细胞浸润,但无神经损伤表现;模型组除可见出血及炎症细胞浸润还有神经受压表现。术后第14天开始对照组出血及炎症细胞浸润明显好转并于术后第21天基本恢复正常;而模型组术后第21天仍可见明显炎症细胞浸润、出现粘连及纤维化表现,并于术后第28天出现较明显的纤维化表现。(3)对照组大鼠TNF-α水平随时间进行明显下降。与对照组比较,模型组血清TNF-α水平在术后各个时间节点均显著升高(P<0.05)。结论采用自体髓核移植法能有效地模拟建立LDH模型。造模术后第21天对照组基本恢复正常而模型组行为学表现、病理学检查及血清TNF-α水平与对照组比较均有明显差异,而在术后第21天之后模型组有恢复的趋势,说明造模术后第21天是比较合适的实验时间节点。

Objective To establish a rat model of lumbar disc herniation(LDH) and dynamically compare the effects of the models at different time points after modeling in order to find the best experimental node after modeling. Methods A total of48 Sprague-Dawley(SD) rats were randomly divided into a control group(a sham operation group) and a model group. LDH rat model was established by autologous nucleus pulposus transplantation in rats. After modeling, the behavioral status of the animals was observed at different time points(days 7, 14, 21, and 28), and the animals were randomly sacrificed for serological and pathological examination. The pathological changes of the nerve tissue in rats were observed by HE staining, and the serum tumor necrosis factor-α(TNF-α) levels were measured by ELISA. Results(1) After modeling, the rats in the model group and the control group(the sham operation group) had obvious symptoms of weakness and lameness in the left hind limb. Starting from the7 thday after surgery, the symptoms in the control group showed a tendency to recover, and basically returned to normal after the14 thday. The symptoms in the model group continued to persist until the 28 thday after surgery.(2) In the control group(the sham operation group), bleeding and inflammatory cell infiltration were seen in the control group(the sham operation group) on the 7 thday after the operation, but no nerve damage was observed;in the model group, in addition to bleeding and inflammatory cell infiltration, there was nerve compression. On the 14 thday after the operation, bleeding and inflammatory cell infiltration in the control group improved significantly and returned to normal on the 21 stday after operation;while in the model group, obvious inflammatory cell infiltration, adhesion and fibrosis appeared on the 21 stday after operation. On the 28 thday after surgery, more obvious fibrosis appeared.(3) Serum TNF-α in the control group decreased significantly over time. Compared with the control group,serum TNF-α level of model group was significantly increased on each time points after modeling(P <0.05). Conclusion The adoption of autologous nucleus pulposus transplantation can effectively simulate the establishment of LDH model. The control group returned to normal on the 21 stday after modeling, and the behavioral performance, pathological examination, and serum TNF-αlevels of the model group were significantly different from those of the control group. However, the model group recovered after21 stday, the trend indicates that the 21 stday after modeling is a more appropriate experimental time point.