Ⅱ型胶原在兔股骨头软骨炎中的变化及机制研究

Experimental study on expression and mechanism of type Ⅱ collagen in juvenile rabbit with Perthes disease

目的:观察Perthes病模型股骨头骺软骨Ⅱ型胶原及血清抗体的变化,探讨Perthes病的发病机制。方法:选择经X线拍片证实双侧股骨头骺板完整无损且未闭合骨化的健康新西兰长耳白兔30只,雌雄各半,随机分为对照组(10只),实验组(20只)。分别于造模后4,6,8,10,12周行右侧髋关节屈曲位X线检查,随后取右侧股骨头用免疫组化法观察Ⅱ型胶原和收集血清检测Ⅱ型胶原抗体浓度。结果:实验组软骨内型胶原结构排列紊乱,数量明显减少,第6～12周实验组与对照组有显著性差异(P<0.05或P<0.01)。Ⅱ型胶原血清抗体浓度测定发现在第6～12周时实验组与对照组之间均有极显著性差异(P<0.01)。结论:骨骺型胶原在Perthes病程中出现先增多后降低的变化过程;且型胶原刺激产生相应抗体发生特异性免疫反应,导致自身免疫攻击,参与Perthes病的发病过程。

Objective：To investigate the Ⅱcollagen expression in epiphysial cartilage of femoral head and its sera antibody level in juvenile rabbits with Perthes disease for exploring the pathogenesis of Perthes disease.Methods：30 health Newzealand white rabbits（half respectively male and female） with hibateral complate and non-ossific epiphysial cartilage of femoral head identified by X-rays image were divided randomly into control group（n=10）and model group（n=20）.Animals in two groups both received sterile operation with semiflexion body position of right hip joint.Juvenile rabbits with Perthes disease were made by injecting 0.5ml TH masic to distal of epiphyseal plate via cutis and centre of collum femoris to with 12 transfixion pin under the radio monitoring.Rabbits in control group were injected with 0.5ml normal sodium with the same method.Rabbits in batch were killed in 4,6,8,10,12w after X rays imaging.Ⅱcollagen in femoral heads were observed by immunohistochemical staining.The levels of Ⅱcollagen antibody in serum were detected by enzyme linked immunosorbent assay（ELISA）.Results：The Ⅱcollagen construction of cartilage arranged disorderly and diminished obviously.The histological results had significant difference between model group and control group from 6w to 12w（P0.05,or P0.01）.The levels of Ⅱcollagen antibody in serum in model group were higher significantly than those in control group（P0.01）.Conclusion：Ⅱcollagen in osteoepiiphysis increased initially and then decreased gradually in developing course of Perthes disease.Ⅱcollagen stimulated to bring about corresponding antibody,then exposed in immune system and led to autoimmunity attack,which maybe involve in the pathogenesis of Perthes disease.