化学神经根炎症模型大鼠的制备及评价

A chemical radiculitis model in the rat: establishment and evaluation

背景:化学神经根造模实验优化为椎间盘的研究提供稳定的动物模型。目的:探索甲醛浸泡滤纸诱发腰椎间盘突出-化学性神经根炎症大鼠模型构建方法,寻找最佳手术造模方案及造模浓度。方法:先将10只由北京市华阜康生物科技股份有限公司提供的SD大鼠随机分为2组,分别采用咬断棘突及不咬断棘突后,在背根神经加以放置预浸泡4%甲醛滤纸进行造模,并结合行为学观察,确定最适手术造模方案。然后探索不同浓度甲醛溶液浸泡滤纸对造模的影响。将另20只SD大鼠随机分为4组,其中3组15只SD大鼠采用上述确定的手术方案(即咬断棘突横突方案),分别在背根神经放置预浸泡1%,2%,4%甲醛溶液滤纸造模,并以Siegal神经评分、苏木精-伊红染色及相关炎症因子的检测结果综合评价造模效果。结果与结论:与不咬断棘突的大鼠相比,咬断棘突L_4、L_5的大鼠Siegal神经评分及评级明显升高。与正常对照组相比,1%,2%,4%甲醛组大鼠在造模后2-8d时Siegal神经评分及评级明显升高,但仅有2%和4%甲醛组的效果可以维持到2周时,且大鼠神经、肌肉、椎间盘组织内均出现较明显的炎症细胞浸润,血清相关炎症因子水平增高明显。提示改进后的模型制备方法,成模率高、死亡率低、模型稳定,可为后续疾病研究及药物研发提供理想的动物模型。

BACKGROUND: Chemical nerve root modeling experiments provide a stable animal model for studying the intervertebral discs.OBJECTIVE: To explore the establishment of lumbar disc herniation and chemical nerve root inflammation in rats by formaldehyde soaked filter paper, and to find the best operation plan and the solution concentration. METHODS: Ten Sprague-Dawley rats provided by Beijing Huafukang Bioscience Co., Inc., in China were randomly divided into two groups and subjected to biting off the spinous process or not. Then, 4% formaldehyde soaked filter papers were placed beside the dorsal root nerve to make the model. Based on behavioral performance, the optimal surgical plan was determined. Thereafter, the effect of different concentrations of formaldehyde soaked filter papers on the modeling. Another 20 Sprague-Dawley rats were randomized into 4 groups, 15 of which were subjected to the above-determined surgical plan of biting off the spinous process, and 1%, 2% and 4% formaldehyde soaked filter papers were placed beside the dorsal root nerve. Siegal neurological score, hematoxylin-eosin staining, and measurement of related inflammatory factors were used to assess modeling effects. RESULTS AND CONCLUSION: The Siegal neurological score and grading were significantly increased in the rats with biting off the L4, 5 than those without biting off the spinous process. Compared with the control group, the Siegal neurological score and grading were markedly increased in 1%, 2%, 4% formaldehyde groups at 2-8 days after modeling, but this increasing tendency remained only in the 2% and 4% formaldehyde groups within 2 weeks after modeling. Moreover, significant inflammatory cell infiltrations occurred in the rat's nerve, muscle and intervertebral disc, and the levels of serum related inflammatory factors increased remarkably. These findings indicate that the improved modeling method has high successful rate and low mortality, which can provide ideal animal models for subsequent diseases and drug researches.