关节软骨撞击伤后软骨细胞凋亡的实验研究

[目的]用TUNEL标记法和透射电镜来观察软骨撞击伤后软骨细胞凋亡的演变情况。[方法]56只健康成年新西兰大白兔,随机分高、低能量两组,每组28只,随机选取一侧后肢为实验组,另一侧为对照组;不同重量的击锤撞击股骨内侧髁软骨面致不同的损伤。术后4 d,1、2、4、8、16、32周收集标本,每个时间组4只兔子,进行TUNEL标记法和透射电镜来观察软骨细胞的凋亡。[结果]对照组标本中在软骨的中间层和钙化层,出现凋亡细胞。低能量组中,伤后4 d,1、2周的标本中,软骨的移形层和过渡层出现凋亡细胞,细胞凋亡率与对照组之间无统计学意义;4周后的标本中凋亡细胞明显减少,细胞凋亡率与对照组之间无统计学意义。高能量组中,伤后4 d软骨浅表层和移形层中出现凋亡细胞,而且伤后时间越长凋亡细胞所占比率越大,细胞凋亡率与对照组之间有统计学意义。[结论]软骨高、低能量撞击伤后早期软骨细胞均出现凋亡,凋亡率高于对照组;但低能量伤后4周软骨细胞凋亡率恢复到对照组水平;高能量伤后软骨细胞凋亡率随时间逐渐增高。

Study of chondrocyte apoptosis after impacting injury of articular cartilage

[Objective]To observate the successive status of chondrocyte apoptosis after impacting injury of articular cartilage by TUNEL marking method and transmission electron microscope(TEM).[Method]Fifty-six New Zealand adult rabbits were divided randomly into low-energy and high-energy two groups,each group was 28.Femoral medial condylar cartilage of one side was injuked by impacting in experimental group,the opposite side as control group.Four rabbits were killed and their medial femoral condylar cartilages were taken at each of the following intervals:4 days,1,2,4,8,16,32 weeks after impacting injury.The specimens were observed as pathology histological sections and strained by TUNEL to measured the rate of chondrocyte apoptosis.[Result]In early stage of post-injury,the rate of chondrocyte apoptosis in and high-energy is significantly higher than that of control group.After 4 weeks,the rate of chondrocyte apoptosis decreases to the level of that of control group in low-energy.In high-energy group,the rate of chondrocyte apoptosis is constantly upgraded-phase,higer significantly than the level of that of control group.[Conclusion]In early stage of post-injury,the rate of chondrocyte apoptosis in low and high-energy was significantly higher than that of control group.After 4 weeks,the rate of chondrocyte apoptosis decreased to the level of control group in low-energy.In high-energy group,the rate of chondrocyte apoptosis is constantly upgraded-phase,higer significantly than the level of control group.