软骨终板细胞凋亡与颈椎间盘退变关系的研究

The Study of the Relationship between Apoptosis of Endplate Chondrocytes and Degeneration of the Cervical Intervertebral Disc

目的:探讨脊柱软骨终板细胞凋亡与颈椎间盘退变之间的关系。方法:24只清洁型wista大鼠,随机分为实验组和对照组。实验组沿C1-C7棘突做正中切口,剥离椎旁肌,切除C1-C7的棘上、棘间韧带及两侧关节突关节后外1/2,诱发加速脊柱退变;对照组仅切开皮肤后缝合。分别于第9周、18周、36周对两组动物施行过度麻醉处死,完整取下包含上下椎体的椎间盘。对颈椎标本行矢状位切片,分离软骨终板和椎间盘。颈椎间盘按Thompson椎间盘退变病理分级标准进行分级评定;将软骨终板石蜡包埋,切片。HE染色和Tunnel染色后,计数椎间盘软骨终板凋亡数量,评估软骨终板消失状况。结果:两组软骨终板细胞凋亡随时间进展而加速。与对照组相比,18周实验组软骨终板细胞凋亡率明显增高(P<0.05);在9周和27周时,实验组与对照组软骨终板细胞凋亡率无统计学差异。结论:脊柱退变模型显著增加了软骨终板细胞凋亡数量,加速了脊柱退变;随年龄增加,软骨终板凋亡细胞数量逐渐增加,软骨终板破坏程度增加,颈椎间盘退变过程加速;年龄是颈椎间盘退变的重要因素;软骨终板细胞凋亡是椎间盘发生退行性变的重要原因。

Objective： To study the relationship between apoptosis of endplate chondrocytes and degeneration of the cervical intervertebral disc. Methods： 24 mice were divided into experimental group and control group randomly. The experimental group model was established by resection all supraspinous and interspinous ligaments of cervical spine, excision of parts of zygapophysial joints,the posterior paravertebral muscles were also detached from posterior elements of the spine, accelerating disc degeneration. The control group was incised only the skin. At each time period of 9 weeks, 18 weeks and 36 weeks after surgery, mice were killed by over anesthesia, to get all the vertebra completely, the sample were cut in midsagittal direction. To separating the disc and endplate chondrocytes. Cervical discs were evaluation according to Thompson criterion. Endplate sections were stained with Tunel procedure. The number of apoptotic cells and vital cells were counted, the degree of degeneration were evaluated. Results：Cell apoptosis of cartilaginous endplate increased with age in experimental group and control group. In 18th weeks,Cell apoptosis of experimental group more serious than controls group（p〈0.05）. In 9 weeks and 27 weeks, there were no obvious difference between experimental group and control group. Conclusion： Disc spondylosis animal model accelerated degeneration, quantity of apoptosis cells increasd; Apoptosis cells of endplate chondrocytes gradually increased, more and more endplate bad destroyed, the degenerated progress also accelerated. So we considered that aged is the important factor for intervertebral discs degeneration;Apoptosis of endplate chondrocytes is the important reason for intervertebral discs degeneration.