兔实验性骨性关节炎早期软骨下骨板的变化

目的 观察兔膝骨性关节炎软骨下骨板与关节软骨之间联系,同时探讨应用降钙素手段干预软骨下骨板对骨性关节炎中关节软骨保护作用.方法 雄性日本大耳白兔随机分为3组,每组8只.对照组动物暴露右膝关节前交叉韧带而不予切断;模型组与实验组行右膝关节前交叉韧带切断术,术后实验组给予5 IU/(kg·d)降钙素皮下注射,模型组给予等量生理盐水,于术后8周处死所有动物并取材.关节软骨采用HE染色及Mankin评分、Von Gieson染色和基质金属蛋白酶-13免疫组织化学检测,软骨下骨板采用Von Kossa染色方法 进行组织形态计量学分析.结果 软骨组织形态学HE及Von Gieson染色显示,模型组关节软骨明显损伤,Mankin评分结果 显示,模型组评分显著高于对照组和实验组(P<0.05),实验组评分显著高于对照组(P<0.05);免疫组织化学染色及半定量分析表明,模型组基质金属蛋白酶-13表达显著高于对照组和实验组(P<0.05);模型组软骨下骨板形态被破坏,与对照组和实验组比较差异显著(P<0.05).结论 前交叉韧带切断诱导的骨性关节炎兔膝关节软骨与软骨下骨板组织结构同时被破坏,软骨下骨板与关节软骨间存在紧密关系,降钙素早期干预软骨下骨板,能够保护软骨下骨板组织形态结构,对关节软骨起到部分保护作用,延缓骨性关节炎病理进程.

Changes of the subchondral plate in the early stage of the experimental osteoarthritis in rabbits

Objective To observe the relationship between the subchondral plate and cartilage in the osteoarthritic rabbit knee, and to investigate the effect of calcitonin on subchondral plate to protect cartilage. Methods Male rabbits were randomly divided into three groups(8 animals per group)，control, model, and experiment groups. In the model and experiment groups，anterior cruciate ligament transaction (ACLT) operation was carried out in the right knee joint. After that, rabbits in the experiment group received subcutaneous injections of calcitonin with 5 IU/(kgI>&#/I>8226;d) dosage. Rabbits in the model group were injected saline. All the rabbits were sacrificed after ACLT operation for 8 weeks. The paraffin sections were stained with HE and von Gieson and graded by Mankin’s scale. Immunohistochemical expressions of matrix metalloproteinases (MMP-13) in cartilage were detected by integral absorbance (IA) analyses. The histomorphometry was applied to analyse the subchondral plate at the proximal tibia. Results Analyzed by the Mankin`s scale in cartilage, the scores of the model group were significantly higher than that of the control and experiment group( P <0.05) and the scores of the experiment group were markedly higher than that of the control group( P <0.05). MMP-13 immunochemical staining in the model group showed a significant overexpression in comparison with those in the control group and experiment group( P <0.05). There was a strong difference of IA scores between the control group and experiment group ( P <0.05); There were significant differences in volume, thickness and porosity of the subchondral plate among the three groups( P <0.05). Conclusion The structures of the subchondral plate and cartilage were destroyed in osteoarthritic rabbit knee induced by ACLT operation, and there was a strong relationship between the subchondral plate and cartilage. Calcitonin treatment on the subchondral plate in the early stage of osteoarthritis may partialy provide protection on