发育性髋脱位早期髋臼软骨细胞凋亡与Caspase-3、Bcl-2表达的相关性研究

目的探讨发育性髋关节脱位（development dislocation of the hip，DDH）早期髋臼软骨细胞凋亡与Caspase-3、Bcl-2表达的相关性。方法选取32只4周龄新西兰大白兔，采用兔后肢屈髋伸膝位管型石膏固定制作DDH动物模型。对24只成功模型兔采用TUNEL法检测髋臼软骨细胞凋亡情况；免疫组化法检测软骨细胞中Caspase-3和Bcl-2的表达。Spearman等级相关分析法进行细胞凋亡与Caspase-3、Bcl-2表达的相关性分析。结果实验进行至8周时，显示实验侧髋臼软骨细胞凋亡率（45.23±10．42）％，高于对照侧（8．04±4.35）％，差异有统计学意义（P〈0．05），但随着实验时间的延长，实验侧髋臼软骨细胞凋亡变化不明显；免疫组化结果显示实验侧髋臼软骨细胞Caspase-3和Bcl-2表达的平均灰度值分别为（56．73±7．85）％与（56．73±7．85）％，二者表达高于对照侧（61．45±5．47）％与（52.32±7．99）％，差异有统计学意义（P〈0．05），但随着实验时间的延长，实验侧髋臼软骨细胞凋亡情况变化不明显。相关性分析得Caspase-3表达的灰度值与软骨细胞凋亡率呈负相关（r=-0．896，P〈0．05），Bcl-2表达的灰度值与软骨细胞凋亡率呈正相关（r=0．939，P〈0．05）。结论凋亡相关因子Caspase-3和Bcl-2可能在髋臼发育不良和髋臼软骨退变中参与调控。

Objective To investigate the corelation of the apoptosis and the expression of Caspase-3 and Bcl-2 of the acetabulum ehondrocytes in the early stage of development dislocation of the hip, Methods Thirty two rabbits of 4 weeks old with no restriction on the gender were used in the experiment. The hip was flexured and the left back knee was extended and then fxed with a plaster cast as DDH model group and the right side without fixation as the control group. The apoptosis was detected by TUNEL, and the expression of Caspase-3, Bcl-2 was determined by immunohistochemistry in the acetabulum chondrocytes of 24 successful models. The correlation of apoptosis and the expression of Caspase-3, Bcl-2 was analyzed by the Spearman rank correlation. Results TUNEL Results showed that the apoptosis rate of acetabulum chondrocytes in DDH model group （ 45.23 ±10.42 ） was higher than that in the control group （ 8.04 ±4.35, P〈0.050 ） before 8 weeks. However, after 8 weeks the apoptosis in DDH model group did not change obviously. Immunohistochemical results showed that the expression of caspase-3 and bcl-2 in DDH model group was higher than it in the control group （ 56.73 ±7.85vs61.45 ±5.47 and 56.73 ±7.85 vs. 52.32 ±7.99, respectively; P〈0.05 ） . The caspase-3 expression and the apoptosis rate in acetabulum chondrocytes was negatively correlated （ r=-0.896, P〈0.05 ） , while bcl-2 expression and the apoptosis rate was positively correlated （ r=-0.896, P〈0.05 ） . Conclusion Caspase-3 and bcl-2 may play a role in acetabulum dysplasia and cartilage degeneration.