颈椎终板软骨细胞凋亡的检测及相关意义

目的检测颈椎终板软骨细胞的细胞凋亡指数,探讨其在椎间盘退变中可能的作用机制。方法颈椎间盘终板及髓核取自我院行颈椎前路手术的35例颈椎椎间盘退变患者（退变组）和19例颈椎外伤患者（外伤组）。光镜观察退变组和外伤组终板和髓核的细胞密度,TUNEL法检测两组终板软骨细胞和髓核细胞的细胞凋亡指数,咔唑分光光度法比较两组髓核蛋白多糖含量。结果退变组终板细胞密度较外伤组减少（P〈0.05）,TUNEL染色显示退变组终板细胞凋亡指数为（34.6±16.1）%,外伤组为（20.1±9.3）%,两组间比较差异有统计学意义（P〈0.05）。Pearson相关分析显示,颈椎终板TUNEL染色阳性细胞率与终板细胞密度、髓核蛋白多糖含量之间呈负相关（r=—0.805,P=0.001;r=—0.677,P=0.023）,与髓核TUNEL阳性细胞率之间呈正相关（r=0.758,P=0.003）。结论颈椎退变终板软骨细胞凋亡率较高,推测在椎间盘退变过程中可能发挥重要作用;软骨细胞凋亡可能与髓核细胞凋亡增加、终板细胞密度与髓核蛋白多糖含量降低密切相关。

The detection and its relative significance of the apoptosis of human cervical cartilage endplate

Objective To investigate the apoptosis index of human cervical cartilage endplate, and to explore its possible effects on intervertebral disc degeneration. Methods Cervical disc endplate and nucleus pulposus were extracted from 35 patients with cervical disc degeneration （degeneration group） and 19 patients suffered from cervical spinal trauma （control group） who performed anterior cervical vertebral surgery in our hospital. The cell density of cervical cartilage endplate and nucleus pulposus was observed by light microscope respectively, and apoptotic cell indexes of endplate and nucleus pulposus were detected with TUNEL method in two groups. Then the content of proteoglycans in nucleus pulposus was compared between two groups with carbazole spectrophotometric method. Results The cell density in cervical endplate was lower in degeneration group than that in control group （P 0.05）. TUNEL staining showed that the apopotic cell indexes of endplate were （34.6 ± 16.1）% in degeneration group while （20.1 ± 9.3）% in control group, there was statistical difference between two groups （P 0.05）. Pearson analysis indicated that TUNEL staining positive rate of endplate was negatively related with the cell density of endplate and the content of proteoglycan in nucleus pulposus （r = —0.805, P = 0.001; r = —0.677, P = 0.023）, and positively related with TUNEL staining positive rate of nucleus pulposus （r = 0.758, P = 0.003）. Conclusions There are much more apoptotic cells in cervical cartilage endplate of degenerative cervical disc which may play a important role during the disc degeneration. Apoptosis changes in cervical cartilage endplate may be related to the apoptosis increase in nucleus pulposus, cell density decrease in endplate as well as the proteoglycan content reduction in nucleus pulposus.