母鼠孕早期铅暴露致后代牙胚中Cbfα1基因的表达

Cbfα1 gene expression in the dentary germ of rat offspring due to lead exposure in early gestation

目的观察母鼠妊娠早期铅暴露后幼鼠牙胚Cbfα1的表达变化。方法 30只受孕母鼠随机分成3组(每组10只),对照组孕早期低剂量组(60 mg/kg)和孕早期高剂量组(240 mg/kg),即于受孕第0天给去离子水或醋酸铅直至仔鼠断乳,在幼鼠生后第2、4、8、10天将幼鼠拉颈处死,分离解剖含下颌第1磨牙区的下颌骨,用新鲜配制4%多聚甲醛固定过夜,梯度乙醇脱水,石蜡包埋,近、远、中向5μm连续切片,常规HE染色+Power VisionTM二步法进行免疫组化制片,观察牙胚发育情况。结果病理组织学可见牙胚随着铅暴露剂量的增加,釉质层变薄,甚至消失。免疫组化结果提示Cbfα1基因的表达受到了影响。结论母鼠孕早期铅暴露致后代牙胚中Cbfα1基因的表达受到明显抑制。

[Objective]To investigate the Cbfal gene expression in the dentary germ of rat offspring due to lead exposure in early gestation.[Methods]A total of 30 pregnant SD rats were divided into 3 groups randomly（10 for each group）： control group,low level lead group（60 mg/kg） and high level lead group（240 mg/kg）.The 3 groups from the gestation to the weaning of rat offspring were given either deionized water or lead acetate.After birth 2 d,4 d,8 d,10 d,the rat offspring were killed by pulling the neck.and their bilateral mandibular under first molar with surrounding alveolar bone were taken out,then the tissues were fixed with 4% paraformaldehyde over night,dehydrated,embedded in paraffin and serially sectioned at 5 μm.Immunohistochemical assay（HE staining ＋ Power VisionTM）was adopted to determine the dentary germ development.[Results]Pathological histology analysis showed adamantine layer thinningz even disappearance with the lead exposure in test group.Immunohistochemical assay showed the Cbfα1 gene expression was suffered influence.[Conclusion]The Cbfal gene expression is obviously inhibited in the dentary germ of rat offspring due to lead exposure in early gestation.