Related Experiment Video
Updated: Aug 24, 2026
Establishment and Validation of a Rat Model of Pulmonary Arterial Hypertension Associated with Pulmonary Fibrosis
Published on: May 23, 2025
Pulmonary elastin expression is decreased in the nitrofen-induced rat model of congenital diaphragmatic hernia
George B Mychaliska1, Susan M Officer, Catherine K Heintz
1Division of Pulmonary and Critical Care Medicine, Washington University School of Medicine, St Louis, MO, USA.
Insights
Congenital diaphragmatic hernia (CDH) in rats leads to reduced and disorganized pulmonary elastin, impacting lung development. This suggests altered mechanical forces may regulate elastin expression in CDH.
Area of Science:
- Pulmonary Medicine
- Developmental Biology
- Extracellular Matrix Research
Background:
- Congenital diaphragmatic hernia (CDH) causes underdeveloped lungs and high blood pressure in the lungs.
- Elastin, a key extracellular matrix protein, is vital for lung development and function.
- CDH lungs exhibit immaturity and reduced compliance, suggesting potential elastin abnormalities.
Purpose of the Study:
- To investigate elastin deposition and organization in a nitrofen-induced rat model of CDH.
- To determine if elastin content and distribution are altered in fetal lungs affected by CDH.
Main Methods:
- Nitrofen was administered to pregnant rats to induce CDH in fetuses.
- Fetal lungs were analyzed for elastin content (desmosine analysis), mRNA expression (Northern blot), and distribution (Hart's staining).
- Three groups were studied: control, nitrofen-exposed without CDH, and nitrofen-exposed with CDH.
Main Results:
- Elastin content was significantly reduced in CDH fetal lungs compared to controls (P =.026).
- mRNA expression of elastin was decreased in CDH lungs.
- Hart's staining revealed less elastin deposition and disorganized distribution in CDH lungs.
Conclusions:
- Pulmonary elastin expression is decreased and disorganized in the nitrofen-induced rat model of CDH.
- The reduction in elastin appears to be regulated at the transcriptional level.
- Altered mechanical forces may play a role in mediating elastin expression in CDH.
Background/Purpose:
Babies with congenital diaphragmatic hernia (CDH) suffer from pulmonary hypoplasia and pulmonary hypertension. Elastin is a critical component of the extracellular matrix (EM) involved in pulmonary development and mechanics. Because CDH lungs are developmentally immature and have reduced compliance, the authors hypothesized that elastin deposition would be reduced and disorganized in the nitrofen rat model of CDH.
Methods:
Time-dated pregnant Sprague-Dawley rats were fed 100 mg of nitrofen on day 9 of gestation. Control rats did not receive nitrofen. The authors analyzed three groups of rats (n = 10 for each group): (1) control (C), (2) nitrofen no CDH (NC), and (3) nitrofen-induced CDH (CDH). On day 21.5 (term, 22 days), the fetuses were delivered by cesarean section, and the fetal lung was harvested. Elastin content, mRNA expression, and distribution were assessed with desmosine analysis, Northern blot analysis, and Hart's staining, respectively.
Results:
The mean desmosine content in picomole desmosine per milligram protein (pmD/mgP) +/- SD was 30 +/- 6.8 (C, n = 10), 25.1 +/- 10.1 (NC, n = 10), and 21.6 +/- 6.4 (CDH, n = 10). The comparison between CDH and controls was statistically significant (P =.026). Northern blot analysis showed decreased mRNA expression in the CDH sample. Hart's staining showed developmentally immature CDH lungs with less elastin deposition and disorganized distribution.
Conclusions:
Pulmonary elastin expression is decreased and disorganized in the nitrofen-induced rat model of CDH. The decreased expression appears to be regulated at the level of transcription. Altered mechanical forces may be responsible for mediating the expression of elastin in CDH.
