氟对小鼠釉原蛋白基因表达的影响

Amelogenin gene expression in fluoride-induced mus musculus incisors of mice

目的探讨氟对小鼠釉原蛋白基因表达的影响。方法在建立小鼠中度及重度氟斑牙模型的基础上,应用原位杂交技术检测对照组(饮用去离子水)、低氟组(饮水F-浓度为50 mg/L)、高氟组(饮水F-浓度为150 mg/L)小鼠下切牙发育过程中釉原蛋白mRNA在成釉细胞增殖分化期、分泌期、成熟期的表达情况。结果小鼠釉原蛋白mRNA在成釉细胞增殖分化期表达为阴性,分泌初期细胞内及新生釉基质中开始出现弱阳性表达;至分泌期,细胞内及新生釉基质中均呈强阳性表达;成熟釉质中无釉原蛋白mRNA的阳性表达。低氟组釉原蛋白mRNA在新生釉基质表面呈强弱交替的不均匀表达;高氟组釉原蛋白mRNA在新生釉基质表面及矿化釉质中均呈阳性表达;在成釉细胞分泌期,其表达多次中断。结论氟影响釉原蛋白mRNA在成釉细胞、釉基质中的表达,过高浓度的氟周期性抑制成釉细胞分泌釉基质的功能,从而导致釉质的矿化不全、矿化不均及局灶性缺损。

Objective To study the effect of fluorine on the amelogenin gene expression of mus musculus incisors.Methods On the basis of establishing a model for medium-and high-level dental fluorosis of mus musculus,this research analyzed the space-time expression of amelogenin in inferior incisor growth period of mus musculus by using in situ hybridization.Results Amelogenin mRNA was negative under the microscope in the ameloblast proliferation differentiation period,and it showed weakly positive expression in intra-cellular and new-birth enamel matrix at the initial secretion stage but it showed strongly positive expression in intra-cellular and new-birth enamel matrix when it came to secretion phase.There was no positive expression of amelogenin mRNA at the mature stage.In low-fluorine group（the concentration of F-in drinking water was 50 mg/L）,amelogenin mRNA showed strongly positive and weakly positive expression alternately on the surface of new-birth enamel matrix under the microscope.In high-fluorine group（the concentration of F-in drinking water was 150 mg/L）,amelogenin mRNA showed positive expression on the surface of dentoenamel junction of new-birth enamel matrix and mineralized enamel under the microscope.Conclusion Overdose fluorine can affect the expression of amelogenin mRNA of ameloblast and enamel matrix,and it can intermittently influence the exudation of enamel matrix at the same time.Then,it will induce ill mineralization of enamel,unsymmetrical mineralization and focal damnification.