Axin2、Wnt5a以及Shh基因在小鼠磨牙胚帽状期中的表达

目的研究Axin2、Wnt5a以及Shh基因在小鼠下颌第一磨牙发育帽状期的表达,初步探讨Wnt与Shh信号通路在牙胚发育中的作用。方法制备小鼠下颌第一磨牙胚帽状期标本,用H-E染色组织学观察磨牙胚帽状期的特点,同时用原位杂交检测Axin2、Wnt5a以及Shh基因的表达部位及强度。结果光镜下可看到磨牙胚帽状期的典型釉结节,周围牙胚间充质细胞聚集,Axin2与Shh基因主要表达于釉结节,而Wnt5a基因主要表达于牙胚间充质。结论经典和非经典的Wnt信号系统以及Shh信号系统在牙胚发育帽状期有各自的表达特点,提示它们可能在牙胚形态发生的调控起着重要的作用。

Expressions of Axin2, Wnt5a and Shh at Cap Stage during Development of Mouse Molar

Objective To investigate the expression of Axin2,Wnt5a and Shh mRNA at cap stage during the development of mouse lower first molar.Methods E14.5 embryonic heads were harvested and 10 μm serial sections for histological observation were made.Tooth germs stained with H-E were observed under the microscope.Axin2,Wnt5a and Shh mRNA were detected by in situ hybridization.Results Typical histological characteristic of molar germ at cap stage was found.Axin2 and Shh mRNA were expressed in the enamel knot,and Wnt5a mRNA was mainly restricted in dental mesenchyme.Conclusion Canonical and noncanonical Wnt signaling molecules and Shh mRNA can be expressed in different manners at cap stage in the developing mouse molar,indicating their essential roles in the regulation of tooth morphogenesis.