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Mouse Embryonic Lung Culture, A System to Evaluate the Molecular Mechanisms of Branching
Published on: June 30, 2010
Nitric oxide modulates branching morphogenesis in fetal rat lung explants
Stephen L Young1, Katherine Evans, Jerry P Eu
1Duke University and Durham Veterans Affairs Medical Centers, Durham, North Carolina 27705, USA. stephen.young@duke.edu
American Journal of Physiology. Lung Cellular and Molecular Physiology
|February 13, 2002
Summary
Nitric oxide (NO) enhances lung development by increasing airway branching in fetal rat lungs. This finding suggests NO plays a crucial role in lung morphogenesis.
Area of Science:
- Pulmonary Medicine
- Developmental Biology
- Cellular Signaling
Background:
- Developing lung cells express nitric oxide synthases (NOS) I and III.
- Nitric oxide (NO) is known to regulate pulmonary blood flow at birth.
- NO's effects on cellular processes suggest a role in lung development.
Purpose of the Study:
- To investigate the role of NO in lung branching morphogenesis.
- To determine if NO donors can modulate airway development in fetal rat lungs.
Main Methods:
- Lung explants from gestational day 13 rat fetuses were cultured.
- Explants were exposed to varying doses of NO donors (NONO-ates).
- Airway branching was quantified over 72 hours.
Main Results:
- A specific long half-life NONO-ate significantly increased lung airway branching twofold.
- The effect was not replicated by cyclic guanine monophosphate analogs.
- Non-specific NOS inhibitors at high concentrations inhibited branching.
Conclusions:
- Endogenous and exogenous NO can modulate branching morphogenesis in the developing rat lung.
- NO is a significant factor in regulating lung development.
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