Electronic Thesis and Dissertation Repository


Master of Science




Bütter, Andreana

2nd Supervisor

Regnault, Timothy R.H.



Purpose: Tracheal occlusion (TO) reverses pulmonary hypoplasia (PH) in congenital diaphragmatic hernia (CDH), but its effect on epithelial-mesenchymal transition (EMT) in lung development remains poorly understood. The purpose of this study was to a) confirm the CDH rabbit model produced PH which was reversed by TO and b) determine the effects of CDH +/- TO on EMT pathways.

Methods: CDH was created at 23 days, TO at 28 days and lung collection at 31 days gestation in fetal rabbits. Lung body weight ratio (LBWR), mean terminal bronchiole density (MTBD), and expression of mRNA and micro-RNA was determined.

Results: Fifteen CDH, 15 CDH+TO, 6 sham CDH, and 15 controls were included in the study. LBWR was low in CDH while CDH+TO was similar to controls. MTBD was higher in CDH fetuses and restored to control levels in CDH+TO. miR-33 and MKI67 were increased following TO, while Lgl1 was decreased in CDH+TO.

Conclusion: TO reversed PH and stimulated early Wnt signaling in CDH fetal rabbits.