牙本质基质蛋白1基因敲除鼠的下颌骨和髁突表型特征的初步研究

The preliminary study on the characteristics of mandible and condyle in dentin matrix protein-1 gene knockout mice

目的研究牙本质基质蛋白1(Dmp1)基因敲除(Dmp1-/-)鼠下颌骨和髁突表型特征,探讨Dmp1在骨和软骨形成及矿化中的作用。方法Dmp1-/-鼠在出生时及出生后2周、2、3、5个月处死并分离下颌骨,行大体观察、X线、透射电镜和组织学观察,比较Dmp1-/-鼠与野生鼠在骨发育、骨密度、组织学上的差异。结果Dmp1-/-鼠下颌骨和髁突出现骨化不全、密度减低、体积减小和髁突软骨退变等变化。结论Dmp1是生长板和继发性骨化中心形成的关键因子,在软骨、骨形成和骨结节塑形中发挥重要作用。Dmp1可能是调控下颌骨及髁突软骨发育的候选基因。

Objective To study the characteristics of mandible and condyle in Dmp1 gene knockout mice, and to investigate the role of Dmp1 in the osteogenesis and mineralization of bone and cartilage.Methods Dmp1-/- mice were executed at birth,2 weeks, 2 months, 3 months and 5 months, and the mandible was taken out for physical, radiography, transmission electron microscopic,and histological examination. The difference between Dmp1 knockout mouse(ko)and wild type mouse(wt)in bone development, bone densitometry and histology were compared.Results There were obvious changes in the mandible and condyle of Dmp1-/- mouse, such as incomplete ossification, low density, decreased volume and condyle cartilage degeneration. Conclusions Dmp1 is the key factor in the formation of growth plates and secondary ossification center, and plays an important role in the process of bone and cartilage formation and bone nodule remodeling. Dmp1 may be the candidate gene that controls the development of mandible and cartilage.