高氟对大鼠口腔粘膜细胞增殖周期和DNA合成的影响

目的研究高氟对大鼠口腔粘膜细胞增殖周期和DNA合成的影响。方法雄性SD大鼠饮用含150mg／LNaF的蒸馏水溶液4周，用流式细胞术研究大鼠口腔粘膜细胞增殖周期和DNA相对含量(DNARC)，用单细胞凝胶电泳检测DNA损伤。结果高氟能引起大鼠口腔粘膜细胞增殖周期的改变，使G2／M期细胞明显下降，DNARC也显著下降，DNA损伤率明显升高。另外，高氟也造成口腔粘膜组织的氧化应激，活性氧族、脂质过氧化产物显著增高，还原型谷胱甘肽明显下降。结论高氟不仅改变了大鼠口腔粘膜细胞的增殖周期，还造成氧化应激，引起DNA损伤并影响DNA合成使DNA相对含量显著下降。

Effects of excessive fluoride on oral mucosal cell DNA synthesis and cell cycle changes in rats

Objective To explore effects of excessive fluoride on oral mucosal cell DNA synthesis and cell cycle changes in rats. Methods Two groups of male SD rats were provided with deionized drinking water containing 0(control group) and fluoride(150 mg/L sodium fluoride) respectively for 4 weeks. Oral mucosal cell DNA damage was measured with single cell gel electrophoresis(or comet assay), DNA relative content(DNA RC ) and cell cycle were detected with flow cytometry. Results Excessive fluoride could reduce the cell number of G 2/M period in cell cycle and decrease DNA relative content significantly in rat oral mucosa. In addition, excessive fluoride could induce rat oral mucosal oxidative stress. The DNA damage rates of excessive fluoride group were 50.20% in oral mucosal cells and were higher than that of the control group significantly. Conclusions It was suggested that excessive fluoride could induce cell cycle changes, decrease DNA relative content and result in oxidative stress and DNA damage in rat oral mucosal cells in vivo.