Abstract:

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 culturedin vitro. The differentia- tion was investigated through microscope and transmission electron microscope under condition of the palatal shelves fusion.Re- sults　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.

Key words: cleft palate, palatal shelves, dexamethasone