T-2毒素对大鼠切牙成釉细胞凋亡相关基因Bcl-2和Bax表达的影响

Influence of T-2 toxin on expression of Bcl-2 and Bax of ameloblasts in rat's incisor

目的:研究不同剂量T-2毒素对大鼠切牙成釉细胞Bcl-2和Bax表达的影响。方法:选择30只SD大鼠,随机分为3组:对照组,实验组1和实验组2,T-2毒素灌胃剂量分别为每天每公斤体质量0、100、200 ng,每周灌胃6 d,连续灌胃4周后处死,取含牙的下颌骨,沿切牙长轴做5μm连续切片,SABC免疫组化检测成釉细胞Bcl-2和Bax蛋白表达,计算机图像采集积分光密度半定量分析Bcl-2和Bax蛋白表达量,蛋白表达量和积分光密度值成反比。结果:两实验组较对照组分泌期成釉细胞Bcl-2蛋白表达下降,Bax蛋白表达上升,Bax/Bcl-2表达的比值上升,各组间均有显著性差异(P<0.05)。结论:T-2毒素可使大鼠切牙分泌期成釉细胞Bcl-2蛋白表达下降,同时上调Bax蛋白表达。高剂量T-2毒素影响更明显。

AIM ： To investigate the effects of T-2 toxin on the protein expression of Bcl-2-/Bax of amelo-blast in rats＇ incisor. METHODS： Thirty Wistar rats were divided randomly into 3 groups： control （0ng/gBW/day T-2 toxin）, experiment 1 （100 ng/gBW/day T-2 toxin） and experiment 2 （200ng/gBW/day T-2 toxin）. After 4 weeks of treatment, immunohisto-chemistry （IHC） was used to observe the relative intensity of Bax and Bcl-2 expression in the ameloblasts. Quantitative analysis of Bax and Bcl-2 expression was performed with a computer image analysis system. Protein expression values were inversely proportional to integrated optical density values. RESULTS： T-2 toxin treatment resulted in upregulation of Bax protein expression and downregulation of Bcl-2 protein expression in secretory-stage ameloblasts in a concentration dependent manner （P 〈 0.05 ）. Bax/ Bel-2 expression ratio was increased in secretory-stage ameloblasts. CONCLUSION： T-2 toxin dose-dependently decreases the expression of Bcl-2 and increases the expression of Bax in the secretory-stage ameloblasts of rat＇s incisor.