【作者】 李媛；

【导师】 张颖丽；

【作者基本信息】 吉林大学 ， 口腔临床医学， 2018， 硕士

【摘要】 目的:研究细胞极性相关蛋白CDC42(cell division cycle 42)和PAR3(partitioning-defective 3 homolog)在小鼠牙发育过程中的时空分布,探讨其在牙发育中的可能作用。方法:取胚胎13.5天(embryonic day 13.5,E13.5)、E14.5、E16.5和E18.5的小鼠胚胎以及出生后1天(postnatal day 1,PN1)和PN5的小鼠,分离头部,固定、脱钙、脱水、石蜡包埋、切片,HE染色观察牙发育的组织学表现,采用免疫组织化学染色方法观察CDC42及PAR3在牙发育过程中的表达变化。结果:HE染色观察到E13.5、E14.5、E16.5和E18.5分别为小鼠牙发育的蕾状期、帽状期、钟状早期和钟状晚期,PN1可见分化成熟的成牙本质细胞与成釉细胞,PN5可见小鼠牙冠部发育完成。免疫组化染色发现,CDC42在E13.5、E14.5和E16.5,于小鼠牙胚中有广泛表达,在E18.5时表达较E13.5、E14.5和E16.5减少,在PN1和PN5,主要表达于成牙本质细胞和成釉细胞的分泌端。PAR3弱表达于E13.5和E14.5的小鼠牙胚,在E16.5和E18.5小鼠牙胚上皮处表达显著增强,在PN1和PN5表达较E18.5减弱。结论:CDC42和PAR3表达于小鼠牙发育的整个过程,可能参与了小鼠的牙发育。在牙胚发育的早期,CDC42和PAR3可能参与了小鼠牙胚间充质细胞的增殖及迁移,在E18.5、PN1和PN5可能参与了成牙本质细胞和成釉细胞的分化,尤其在成牙本质细胞和成釉细胞极性的形成与维持中可能具有重要作用。更多还原

【Abstract】 Objectives:To study the expressions of polarity related proteins CDC42 and PAR3 during tooth development in mice and discuss their possible roles during tooth development in mice.Methods:The whole mouse heads were obtained from embryonic day 13.5(E13.5),E14.5,E16.5 and E18.5 embryos and postnatal day 1(PN1)and PN5 mice.The tissues were fixed in paraformaldehyde,decalcified,dehydrated,embedded in paraffin,and sectioned.Histology during tooth development was observed by HE staining.The localizations and changes of CDC42 and PAR3 during tooth development were detected by immunohistochemistry staining.Results:HE staining showed that E13.5,E14.5,E16.5 and E18.5 are the bud stage,cap stage,early and late bell stage of tooth development,respectively;PN1 showed matured odontoblasts and ameloblasts;PN5showed completed tooth crown development.Immunohistochemistry staining showed that CDC42 was expressed in epithelium and mesenchyme during tooth development at E13.5,E14.5 and E16.5.CDC42 expression was reduced at E18.5,comparing with E13.5,E14.5and E16.5.At PN1 and PN5,CDC42 was expressed at the secreting sides of odontoblasts and ameloblasts.PAR3 was weakly expressed at E13.5and E14.5.At E16.5 and E18.5,PAR3 expressions were significantly enhanced.At PN1 and PN5,PAR3 expressions were decreased,comparedwith E18.5.Conclusion:CDC42 and PAR3 participate in mouse tooth development.During the early stage of tooth development,CDC42 and PAR3 may be involved in the proliferation and migration of the tooth mesenchymal cells.At E18.5 、 PN1 and PN5,CDC42 and PAR3 may be involved in the differentiation of odontoblasts and ameloblasts,especially in the establishment and maintenance of cell polarity.更多还原