摘要：
背景:目前虽然纤维环穿刺法构建椎间盘退变模型的相关研究报道较多,但缺乏相对完整的影像、病理学以及细胞外基质改变(蛋白多糖含量)的系统对比性研究.所以经腹膜外入路暴露椎间隙纤维穿刺法造模的影像、病理学以及细胞外基质改变是否与人类椎间盘退变类似需进一步探讨.目的:验证采用纤维环穿刺法建立椎间盘退变模型的可行性.方法:将30只新西兰大白兔随机分为2组,每组15只.纤维环穿刺组在经腹膜外入路暴露L1,2,L2,3,L3,4椎间隙后,采用16号针头穿刺;而假手术组只做切开不做穿刺.于造模术后4,8,16周2组均随机抽取5只行MRI检查后,以空气栓塞法处死兔并切取椎间盘髓核组织,苏木精-伊红染色检查组织学变化,Safranin O染色观察髓核蛋白多糖水平改变.结果与结论:①MRI提示:纤维环穿刺组T2WI相椎间盘信号自造模术后开始降低,且随着术后时间延长T2WI相椎间盘信号降低越明显,于术后4周较假手术组有明显改变,术后16周最明显;假手术组术后各时间段改变不明显;②苏木精-伊红染色显示:纤维环穿刺组造模术后软骨样细胞减少,纤维样细胞增多且所占比例增大,细胞外纤维排列紊乱,于第4周较假手术组有明显改变,于第16周最明显;假手术组术后各时间段改变不明显;③Safranin O染色(髓核蛋白多糖水平):纤维环穿刺组组织着色于造模术后开始变浅,随着术后时间延长着色变浅越明显,于术后4周较假手术组有明显改变,术后16周最明显;④结果提示:纤维环穿刺法建立的椎间盘退变模型影像学表现及病理表现与人类椎间盘退变近似,提示纤维环穿刺法是建立椎间盘退变模型的可靠方法.%BACKGROUND:Annulus puncture method is commonly reported in the establishment of intervertebral disc degeneration (IDD) models, but there is a lack of comparative studies concerning complete MRI, pathologyical and extracellular matrix changes. Thereafter, a further exploration is imperative. OBJECTIVE:To investigate the feasibility of establishing IDD models using annulus puncture. METHODS:Thirty New Zealand white rabbits were randomly divided into two groups (n=15 per group). In experimental group, through extraperitoneal approach, the L1-2, L2-3, and L3-4 intervertebral space were exposed, and then stabbed by 16-gauge hypodermic needles;while rabbits in sham operated group were only subjected to making and incision but not to puncture. Five rabbits in each group were randomly selected for MRI examination at 4, 8 and 16 weeks after modeling, and were sacrificed through air embolism to obtain the nucleus pulposus. Histological changes were observed by hematoxylin-eosin staining, and the level of proteoglycan was detected by Safranin O staining. RESULTS AND CONCLUSION:In the experimental group, T2-weighted signal in the disc was decreased in a time-dependent manner;an obvious reduction was found at 4 weeks after modeling, and reached the peak at 16 weeks. In contrast, the sham operated group showed no significant changes at each time point. Hematoxylin-eosin staining showed that in the experimental group, cartilage-like cells decreased, while fibroblast-like cells in the disc increased in number and proportion, and extracellular fibers were in disorder;all above changes became obvious at 4 weeks after surgery and the most obvious at 16 weeks, but there were no significant changes in the sham operated group. Safranin O staining revealed that the color of the tissues under puncture became lighter, and this variation became overt at 4 weeks after surgery and the most obvious at 16 weeks. In conclusion, annulus puncture is a reliable method to make IDD models.
