地塞米松对体外培养A系小鼠腭突腭中嵴上皮融合的影响

目的　研究在腭间充质存在的情况下,地塞米松对腭中嵴上皮细胞分化、转归的影响,以探讨地塞米松引 起腭裂畸形的发病机制。方法　A系小鼠妊娠14 d 8 h在体视显微镜下,解剖分离出A系小鼠胚胎腭突,应用半浸 静式腭突体外培养方法,通过光学显微镜和透射电镜观察在腭突接触融合时,地塞米松对腭中嵴上皮细胞的影响。 结果　地塞米松促进了腭中嵴上皮分化成复层鳞状上皮,加速了腭间充质分化过程,影响了腭突的正常发育,阻碍 腭突融合。结论　地塞米松可能通过加速腭间充质分化和抑制腭中嵴上皮正常转归的双重作用,阻碍腭的正常发 育过程,导致腭裂畸形。

Influence of Dexamethasone on Fusion of Embryonic Palatal Medial Edge Expithelium in Mouse Palatal Shelves in vitro

Objective To study the effect of dexamethasone on the differentiation and proliferation of type A mouse palatal medial edge epithelial cells when there is type A mouse embryonic palatal mesenchymal cells.Methods The mouse palatal shelves were harvested from a female mouse of gestation day 14 by microsurgical dissection and cultured in vitro. The differentiation was investigated through microscope and transmission electron microscope under condition of the palatal shelves fusion. Results Dexamethasone promoted the palatal medial edge epithelium differentiated into squamause epithelium and affected normal development and obstructed the fusion of mouse palatal shelves. Conclusion The results of histological observation indicate that dexamethasone promotes the proliferation of palatal meseuchymal cells and inhibits the normal differentiation of palatal medial edge epithelial cells, which results in cleft palate.