Many preterm infants require mechanical ventilation as life-saving therapy.
However, ventilation-induced overpressure can result in lung diseases.
Considering the lung as a viscoelastic material, positive pressure inside the
lung results in increased hydrostatic pressure and tissue compression. To
elucidate the effect of positive pressure on lung tissue mechanics and cell
behavior, we mimic the effect of overpressure by employing an uniaxial load
onto fetal and adult rat lungs with different deformation rates. Additionally,
tissue expansion during tidal breathing due to a negative intrathoracic pressure
was addressed by uniaxial tension. We found a hyperelastic deformation
behavior of fetal tissues under compression and tension with a remarkable
strain stiffening. In contrast, adult lungs exhibited a similar response only during
compression. Young’s moduli were always larger during tension compared to
compression, while only during compression a strong deformation-rate
dependency was found. In fact, fetal lung tissue under compression showed
clear viscoelastic features even for small strains. Thus, we propose that the fetal
lung is much more vulnerable during inflation by mechanical ventilation
compared to normal inspiration. Electrophysiological experiments with
different hydrostatic pressure gradients acting on primary fetal distal lung
epithelial cells revealed that the activity of the epithelial sodium channel
(ENaC) and the sodium-potassium pump (Na,K-ATPase) dropped during
pressures of 30 cmH2O. Thus, pressures used during mechanical ventilation
might impair alveolar fluid clearance important for normal lung function.
| Identifer | oai:union.ndltd.org:DRESDEN/oai:qucosa:de:qucosa:88053 |
| Date | 15 November 2023 |
| Creators | Naumann, Jonas, Koppe, Nicklas, Thome, Ulrich H., Laube, Mandy, Zink, Mareike |
| Publisher | Frontiers Media S.A. |
| Source Sets | Hochschulschriftenserver (HSSS) der SLUB Dresden |
| Language | English |
| Detected Language | English |
| Type | info:eu-repo/semantics/publishedVersion, doc-type:article, info:eu-repo/semantics/article, doc-type:Text |
| Rights | info:eu-repo/semantics/openAccess |
| Relation | 10.3389/fbioe.2022.964318 |
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