兔椎体软骨终板血管芽增龄性变化

目的 探讨不同年龄段兔椎体软骨终板内血管芽的形态变化与椎间盘退变的关系.方法 15只不同年龄段新西兰兔,2月龄5只,1年龄5只,3年龄5只,雌雄不限.X线观察终板有无钙化及椎体周围有无骨赘形成,组织学观察软骨终板和椎间盘的形态学变化,血管铸型后扫描电镜观察终板各部位血管的形态变化.按Miyamoto等分级标准将椎间盘分为1～5级,分别规定为1～5分.采用t检验,分别对2月龄组和1年龄组髓核区与内层纤维环区,2月龄组及1年龄组兔髓核区、内层纤维环区椎体终板内血管直径进行比较.结果 2月龄组终板无明显钙化、软骨终板结构良好、潮标清晰,髓核及纤维环结构饱满清晰;1年龄组终板轻度钙化,髓核皱缩,纤维环出现裂隙;3年龄组终板钙化明显,密度增高,并可见骨赘形成,髓核消失.随着年龄增加,终板内微血管逐渐减少,最终消失,软骨终板中心部位较周围部血管减少更为明显.组织学显示软骨终板出现钙化,软骨终板退变重于椎间盘;钙化的程度与椎间盘退变程度呈正相关.2月龄组髓核区与内层纤维环区椎体终板内血管直径比较,差异有统计学意义;2月龄组与1年龄组髓核区椎体终板内血管直径比较,差异有统计学意义.结论 随着兔年龄增加终板内血管逐渐减少,终板发生退变,其程度重于椎间盘,提示椎体终板内微血管的变化可能是椎间盘退变的重要促进因素.

Abstract：

Objective To observe the morphologic changes of of vascular buds in vertebral cartilage endplate in age-specific rabbits and also to investigate the correlation between the changes of vascular buds and interverbral disc degeneration. Methods There were 15 New Zealand white rabbits in our study,which include three groups, 2-week-old rabbits, 1-year-old rabbits and 3-year-old rabbits, and each groups had five rabbits. The X-ray radiograph, histology and scanning electron microscope were used to observe the changes of vertebral cartilage endplate. According to Miyamoto standard, the interverbral disc was graded 1-5, and scored 1-5 respectively. Results The changes of micro-vascular structure of vertebral cartilage endplate were observed during aging. Under the scanning electron microscope, the vascular structure degenerated gradually, and disappeared in the end. The blood vessels in the central region of the vertebral cartilage endplate reduced more obviously than those in periphery region. The severe degeneration was found in vertebral endplate, compared with intervertebral disc. The changes of vascular buds in rabbits vertebral cartilage endplate had positive correlation with the vertebral endplate calcification and the interbertebral disc degeneration. Conclusion Changes of vascular buds in vertebral endplate may accelerate intervertebral disc degeneration.

Morphologic differences of vascular buds in vertebral cartilage endplate in age-specific rabbits

Objective To observe the morphologic changes of of vascular buds in vertebral cartilage endplate in age-specific rabbits and also to investigate the correlation between the changes of vascular buds and interverbral disc degeneration. Methods There were 15 New Zealand white rabbits in our study,which include three groups, 2-week-old rabbits, 1-year-old rabbits and 3-year-old rabbits, and each groups had five rabbits. The X-ray radiograph, histology and scanning electron microscope were used to observe the changes of vertebral cartilage endplate. According to Miyamoto standard, the interverbral disc was graded 1-5, and scored 1-5 respectively. Results The changes of micro-vascular structure of vertebral cartilage endplate were observed during aging. Under the scanning electron microscope, the vascular structure degenerated gradually, and disappeared in the end. The blood vessels in the central region of the vertebral cartilage endplate reduced more obviously than those in periphery region. The severe degeneration was found in vertebral endplate, compared with intervertebral disc. The changes of vascular buds in rabbits vertebral cartilage endplate had positive correlation with the vertebral endplate calcification and the interbertebral disc degeneration. Conclusion Changes of vascular buds in vertebral endplate may accelerate intervertebral disc degeneration.