A longer tracheal occlusion period results in increased lung growth in the nitrofen rat model

Department of Obstetrics and Gynaecology, Division Woman and Child, University Hospital Gasthuisberg, Herestraat 49, Leuven, Belgium.
Prenatal Diagnosis (Impact Factor: 3.27). 01/2012; 32(1):39-44. DOI: 10.1002/pd.2881
Source: PubMed


Prenatal tracheal occlusion (TO) promotes lung growth and is applied clinically in fetuses with severe congenital diaphragmatic hernia. Limited data are available regarding the effect of duration of TO on lung development. Our objective was to evaluate the effects of long (2 and 2.5 days) versus short (1 day) TO on lung development in rats with nitrofen-induced diaphragmatic hernia.
Nitrofen was administered on embryonic day (ED) 9 and fetal TO performed either on ED18.5, 19 or 20 (term = 22 days). Sham-operated and untouched littermates served as controls. On ED21, lungs were harvested and only fetuses with a left-sided diaphragmatic defect were included in further analyses.
Lung-body-weight ratio incrementally increased with the duration of TO. Increased proliferation following long TO was confirmed by immunohistochemistry and qRT-PCR for the proliferation marker Ki-67. Irrespective of duration, TO induced more complex airway architecture. Medial wall thickness of pulmonary arteries was thinner after long rather than short TO.
In the nitrofen rat model of congenital diaphragmatic hernia, a longer period of TO leads to enhanced lung growth and less muscularized pulmonary arteries.

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    • "ive phases of the cell cycle ( Bullwinkel et al . , 2006 ) . Previous studies showed that Ki - 67 is a reliable marker for proliferative activity in the lungs ( Thomas et al . , 1996 ) . However , data about proliferative role of Ki - 67 in the development of normal human lung are scarce , and the majority of studies used different animal models ( Beck et al . , 2012 ; McDougall et al . , 2011 ) . Only two studies on human fetus investigated the role of Ki - 67 during alve - olar cell differentiation ( Tebar et al . , 2001 ) and hypoplastic lungs ( Dzieniecka et al . , 2013 ) . As a member of the cysteine – aspartic acid protease ( caspase ) family , caspase - 3 plays a key role in the execution - p"
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