过量氟对大鼠切牙Shh表达的影响

Effect of fluorosis on the expression of Shh in rat incisors

目的研究过量氟对大鼠切牙Shh(Sonic Hedgehog)表达的影响,从分子水平探讨氟斑牙的发病机制。方法20只Wistar大鼠随机分为2组:对照组(饮用蒸馏水)和实验组(饮用100mg/L氟化水),复制氟斑牙动物模型,8周末处死动物,获取切牙标本,免疫组化染色观察Shh在大鼠切牙的表达定位及在对照组与实验组切牙表达的变化。结果Shh在分泌期成釉细胞、成牙本质阳性表达。实验组Shh的表达明显弱于对照组,差异有显著性(P<.01)。结论过量氟可能通过抑制Shh的表达,从而影响牙齿发育的启动和随后的细胞分化,导致釉质发育障碍。

Objective To investigate the effects of overdose fluoride on the expression of Shh in rat incisor. Methods Twenty Wistar rats were randomly divided into 2 groups. In group I （ control group） distilled water was given,and in group Ⅱ （experimental group） 100mg/1 NaF was given. The fluorosis model was established , and then the rats were killed at the end of 8th week. Immunohistochemical staining was used to study the expression of Shh in rat incisors. Results Immunohistochemical results demonstrated the presence of Shh in ameloblasts and odontoblasts of rat incisor , the expression of Shh was significantly reduced in group Ⅱ than in group I （P〈.01 ）. Conclusion The overdose fluoride might inhibit the expression of Shh and affect the start of tooth development and cell differentiation, which leads to the enamel demineralization.