苯妥英钠对大鼠牙龈上皮细胞增殖和凋亡的影响

目的观察苯妥英钠(PHT)对大鼠牙龈上皮细胞增殖和凋亡的影响。方法将60只雄性SD大鼠随机分为5组:对照组(腹腔注射灭菌生理盐水1mL)和0、5、25、50、100mg/mL PHT组(腹腔注射上述质量浓度PHT),连续28d;监测PHT血药浓度;29d处死大鼠,制作牙龈组织切片,采用原位脱氧核糖核苷酸末端标记法(TUNEL)检测牙龈上皮细胞的凋亡情况;采用免疫组织化学方法检测牙龈上皮细胞Ki-67的表达。结果实验组凋亡指数(AI)显著低于对照组(P<0.01),而增殖指数(PI)显著高于对照组(P<0.01);PHT血药浓度与AI呈显著负相关(r=-0.98),与PI呈显著正相关(r=0.976)。结论 PHT通过抑制牙龈上皮细胞凋亡和促进细胞增殖,导致牙龈上皮的增生;PHT血药浓度与增生程度可能存在关联。

Effect of phenytoin on proliferation index and apoptosis index of gingival epithelium cells in rats

Objective To evaluate the effect of phenytoin(PHT) on cell proliferation and apoptosis of gingival epithelium cells.Methods Totally 60 SD rats were randomly assigned to five groups: 0(control),5 mg/mL,25 mg/mL,50 mg/mL and 100 mg/mL PHT.All rats were injected through intraperitoneal injection for 28 days and sacrificed on day 29;then gingival tissue slices were made.The number of Ki-67 positive cells and TUNEL-positive cells was determined;the serum PHT level was monitored.Results Compared with those in control group,apoptosis index(AI) was significantly lower in experiment groups than in control group(P<0.01),but proliferation index(PI) was significantly higher(P<0.01) in experiment groups.Serum PHT level had a significantly positive correlation with PI(r=0.976) but a significantly negative correlation with AI(r=-0.98).Conclusion Inhibition of cell apoptosis and active cell proliferation are both involved in gingival epithelium overgrowth;the degree of epithelial hyperplasia gum seems to be related to serum PHT level.