Molecular biological analysis for foregut malformation in a rat model

正常和阿霉素（ADM）致气管食管瘘（TEF）大鼠发育中的前肠三维图像重建。在正常胚胎中，肺芽在第11天出现在咽前肠的正下方，随着它们的生长，它向尾端伸长，形成气管。“气管食管隔”未出现。在TEF胚胎中，虽然肺芽在第11天出现在相似的位置，但气管和食管没有分离，只有一个共同的前肠管尾部伸长，然后在分叉水平直接出现双侧支气管原基。此外，脊索的异常发育也很明显，在与前肠分离时发育迟缓，最终沿着更腹侧的路线下降，并在分叉处急剧弯曲。TEF的发育在第13天基本完成。在正常胚胎中，气管似乎仅由肺芽的尾侧侧索形成。在adm诱导的TEF胚胎中，上前肠似乎只发育成气管，这种发育不良可能与前肠与周围间质之间的异常相互作用有关。

Three dimensional image reconstruction od the developing foregut in normal and adriamycin (ADM)-induced tracheoesophageal fistula (TEF) rats.In the nornal embryo, the lung bud appeared just below the pharyngeal foregut on day 11 and it elongated caudally to shape into the trachea as they grew. A 'tracheoesophageal septum' did not emerge. In the TEF embryos, although the lung bud appeared in a similar position on day 11, trachea and esophagus did not separate and only a common foregut tube elongated caudally, then bilateral bronchial primordia emerged directly at the level of bifurcation. furthermore, abnormal development of the notochord was evident, being retarded in separation from the foregut, finally descending along a more ventral course and bending sharply around the level of the bifurcation. The development of TEF was almost complete by day 13.In sunnary, the trachea seemed to be formed only by caudal elingation of the lung bud in the normal embryo. In the ADM-induced TEF embryos, the upper foregut appeared to develop only into the trachea and dthis maldevelopment may be implicated in the abnormal interaction between the foregut and the surrounding mesenchyme.