【摘要】 目的探讨新西兰兔终板下椎骨注射平阳霉素后对终板下椎骨微循环及椎间盘的影响。方法 15只新西兰兔随机分成3组,每组兔子均经皮穿刺终板下椎骨注射平阳霉素。对腰4/5、腰5/6或腰6/7椎间盘其中一个进行手术(实验组),另两个椎间盘作为对照组不予手术。分别于术后4、12、24周对兔脊柱行MRI检查并处死,行相关组织病理学检测。结果术后4周各组腰椎间盘Pfirrmann分级均为Ⅰ级,实验组术后12周出现Ⅱ级腰椎间盘1例,术后24周出现Ⅱ级腰椎间盘1例和Ⅲ级腰椎间盘1例,对照组仍为Ⅰ级。实验组术后12周发现髓核组织和软骨终板PAS染色和CollagenⅡ免疫组化后的平均光密度值(mean optical density,MOD)均较对照组低(P<0.05),术后24周差异更明显(P<0.01),髓核组织蛋白聚糖含量检测结果与PAS染色结果表现一致。与对照组相比,实验组术后4周时仅终板下椎骨基质金属蛋白酶-1(matrix metalloproteinase 1,MMP-1)表达增高(P<0.05),术后12和24周时终板下椎骨、软骨终板和髓核组织表达均增高(P<0.01),且随时间延长,实验组终板下椎骨、软骨终板和髓核组织MMP-1表达增高(P<0.05)。实验组各时间点终板下椎骨CD34表达均较对照组低(P<0.01),实验组术后12和24周终板下椎骨CD34表达较术后4周高(P<0.05),术后12周与24周比较差异无统计学意义(P>0.05)。HE染色显示实验组术后各时间点终板下椎骨微血管均可见血栓存在,血管与椎骨面积比逐渐减小,随时间延长,终板下椎骨和软骨终板出现退变表现且进行性加重。结论新西兰兔腰椎终板下椎骨注射平阳霉素后可出现终板下椎骨微循环损伤,终板下椎骨和软骨终板发生退变,诱导椎间盘退变。更多还原

【Abstract】 Objective To evaluate the pathological changes of sub-endplate vertebrae and intervertebral disc in New Zealand rabbits induced by sub-endplate vertebrae injecting pingyangmycin. Methods 15 New Zealand rabbits were randomly divided into three groups, and one of intervertebral discs at lumbar 4/5, lumbar 5/6 and lumbar 6/7 was designed for ischemic lumbar intervertebral disc degenerative model and the other two discs for controls. After MRI examination at 4, 12 and 24 weeks after opera-tion, the rabbits were executed humanely and histopathology was performed to evaluate the process of degeneration. Results The Pfirrmann scale of lumbar intervertebral disc in all groups were Pfirrmann Ⅰ at 4 weeks after operation. In the experimental group,the Pfirrmann scale of lumbar intervertebral disk in 1 rabbit was changed to Pfirrmann Ⅱ at 12 weeks and 2 rabbits to Pfirrmann Ⅱand Pfirrmann Ⅲ separately at 24 weeks after modeling but no change in control group. Mean optical density(MOD) of nucleus pul posus and endplate cartilage by Periodic Acid-Schiff(PAS) stain and Collagen Ⅱ immunohistochemistry in the experimental groups showed significantly lower(P<0.05) at 12 weeks after operation than control groups, the difference was more significant at 24 weeks after operation(P<0.01). The results of quantitative determination of proteogly can in the nucleus pulposus were consistent with that of PAS stain. In the experimental group, at 4 weeks after modeling, only the expression of matrix metalloproteinase 1(MMP-1) in subchondral bone enhanced(P<0.05), but at 12 and 24 weeks, the expression of MMP-1 in nucleus pulposus, endplate cartilage and subchondral bone all enhanced significantly( P<0.01). With the extension of observational time, staining intensity gradually in-creased( P < 0. 05), the comparison among the groups also had statistical significance( P < 0. 05). CD34 of sub-endplate vertebrae in the experimental group expressed less than the control group. In the experimental groups, the expression of CD34 of sub-endplate vertebrae at 12 and 24 weeks were more than that at 4 weeks after operation( P<0.05), while the difference of CD34 between 12 and24 weeks after operation had no statistical significance(P>0.05). HE staining confirmed the existence of microcirculation disturbance in sub-endplate vertebrae and with time extended the structure of endplate cartilage and subchondral bone was damaged and degenerated gradually. Conclusion Ischemic change of sub-endplate vertebrae can be induced by injecting pingyangmycin. The cartilage endplate and the sub-endplate vertebrae degenerated gradually, which gave rise to a degenerative disc.更多还原