<div>Purpose: Pulmonary hypoplasia remains a major cause of high mortality in
congenital diaphragmatic hernia (CDH). Notch1 signaling pathway plays a
critical role in alveolar epithelial cells(AECs) differentiation which
dominated in the pulmonary hypoplasia of CDH. However, the effect of
Notch1 pathway in CDH remains unclear. We design this study to
investigate the hypothesis that the aberrant Notch1 pathway leads to the
pulmonary dysplasia in nitrofen-induced CDH rat model. Methods: Pregnant
rats were designed as follows: Control, CDH, CDH+CUR. Morphological,
Immunostaining and qRT-PCR study were performed to determine the
expression levels of T1α and TTF1 in AECs and the expression levels of
gene including NICD1 and Hes1 associated with Notch1 signaling pathway.
Results: Immunostaining of AEC-I marker T1α and AEC-II marker TTF1
showed that the positive area ratio of T1α in CDH group was less in CUR
and Control group, TTF1 was larger in CUR and Control than CDH group
(p&lt; 0.05). NICD1 and Hes1 in CDH group were lager than CUR and
Control group (p&lt; 0.05). qRT-PCR showed that the expression
levels of T1α in CDH group was lower than that in CUR and Control group
(p&lt; 0.05), and TTF1, NICD1 and Hes1 in CDH group were higher
than CUR and Control group (P &lt; 0.05). Conclusion: Aberrant
Notch1 signaling pathway and AECs differentiation disorders are involved
in the pathogenesis of pulmonary hypoplasia in nitrofen-induced CDH rat
model. Our data suggest that overexpressed Notch1 signaling pathway may
cause pulmonary hypoplasia in CDH by inhibiting the differentiation of
AECs.</div>