不同年龄阶段家兔髂软骨组织学特点

Histological Characteristics of Iliac Crest Cartilage in Rabbits with Different Ages

目的:观察比较不同年龄阶段新西兰大白兔髂软骨组织学形态异同。方法:选取1月龄、3月龄、4月龄、6月龄、12月龄的新西兰大白兔各3只。取其髂软骨及少量软骨下骨做HE染色、甲苯胺蓝染色及I型、II型胶原免疫组织化学染色;同时取1月龄、3月龄和12月龄组膝关节股骨滑车软骨做相同染色用于对比。结果:①幼年期(1月龄),髂软骨全部由透明软骨组成,随着年龄的增长,4月龄部分表层软骨细胞逐渐肥大、骨化,至成年期全层软骨细胞几乎完全骨化。甲苯胺蓝染色、II型胶原免疫组化染色均显示由幼年时的阳性逐渐减弱为成年时的弱阳性。I型胶原只在骨化区、软骨下骨及肌腱部位着色阳性。②随着年龄增长,关节软骨细胞密度逐渐下降,软骨层厚度逐渐变薄。细胞肥大及骨化发生在钙化层。结论:家兔幼年期髂软骨类似关节透明软骨,随着年龄增长髂软骨细胞逐渐肥大、骨化,至成年期仍有少量透明软骨细胞特有的II型胶原蛋白及蛋白多糖的合成。

Objective To study the histological characteristics of iliac crest cartilage in rabbits model with different ages.Materials and Methods The New Zealand white rabbits were divided into five groups according to age（1-month group,3-month group,4-month group,6-month group and 12-month group,each group contained 3 rabbits）.The iliac crest cartilage was processed for histological（HE and toluidine blue） and immunohistochemical（collagen type I and II）study.Also,the cartilages of knee joints from 1-month,3-month and 12-month groups were evaluated histologically and immunohistochemically for comparison with the iliac crest cartilage.Results ① In infancy,the total portion of the iliac crest cartilage is formed by hyaline cartilage.With increasing of age,the hypertrophy and ossification of some chondrocytes occurred gradually in the middle of the iliac crest cartilage.In adulthood,the whole cartilage was almost ossified.In infancy,the toluidine blue staining and immunohistochemistry display strong positive for proteoglycans and collagen type II respectively.② The cell density and thickness of cartilage reduce with increasing of age.The hypertrophy and ossification of some chondrocytes occur in the deep zone of the cartilage gradually.Conclusion The iliac crest cartilage in infancy is hyaline cartilage-like tissue.With increasing of age,the hypertrophy and ossification of some chondrocytes in superficial zone occur gradually.In the adult age,the whole cartilage is almost ossified.But the indices peculiar to the hyaline cartilage,such as collagen type II and proteoglycans,are still positive in adulthood.