The correlation between TGF-b3 and HGF/SF in the process of fusion of secondary palatal shelves

本研究探讨了胚胎发育过程中调节胚胎期细胞生长的转化生长因子-β与胚胎发育过程中与上皮-间充质转化相关的转化生长因子/肝细胞生长因子(HGF/SF)的相互作用机制。β-β3mRNA在胚胎第12天开始在上皮层和间充质层中表达，12.5天明显表达，13.5天后消失；HGF/SF基因在胚胎第12天开始在间充质层表达，13.5天后表达消失。在器官培养中，HGF/SF反义寡核苷酸处理可抑制小鼠次级腭架的融合，但不能抑制它们的发育。在器官培养中，c-Met中和抗体的处理抑制了小鼠次级腭架的发育。在器官培养中，转化生长因子-β-3反义寡核苷酸抑制了小鼠次级腭突的发育和融合。提示β/SF和转化生长因子-β-3可能在胚胎发育的同一时期表达，在小鼠次级腭突由垂直向水平方向转变时，可能诱导了腭尖细胞的凋亡，转化生长因子-hGF3可能与小鼠次级腭突向水平方向的生长有关。

In this study, we investigated the mechanism of the corrrelation between TGF-β which regulates the cell growth in the embryonic stage anf HGF/SF which is related to epithelial-mesenchymal transformation in the process of the fusion of secondary palatal shelves in organ culture in vitro and vivo.Palate development was examined by H.E. staining on embryonic day 12〜15, and expression of HGF/SF and TGF-β3, Mrna was investigated by whole mount in situ hybridisation on embryonic day 12〜15. In addition, we conducted to examine whether treatment of HGF/SF or TGF-β3 in organ culture.Expression of TGF-β3 Mrna was detected in epithelial and mesenchymal layer from embryonic day 12, and they were observed markedly on embryonic day 12.5, and disppeared after embryonic day 13.5, Expression of HGF/SF Mrna was also detected in mesenchymal layer from embryonic day 12, and disppeared after embryonic day 13.5. Treatment of HGF/SF antisense oligonucleotide prove inhibited the fusion of mouse secondary palatal shelves,but did not inhibit the development of them in organ culture. Treatment of c-Met neutralizing antibody inhibited the development of mouse secondary palatal shelves in organ culture. Treatment of TGF-β3 antisense oligonucleotide prove inhibited the development and fusion of mouse secondary palatal shelves in organ culture.These findings suggested that HGF/SF and TGF-β3 may express at the same embryonic stage, and HGF/SF may induce apoptosis in the tip of the palate at the time which mouse secondary palatal shelves make a change of direction from vertical position to horizontal position, and TGF-β3 may be related with the growth of mouse secondary palatal shelves to the horizontal direction.