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Angiogenesis in the Ischemic Rat Lung
Published on: February 8, 2013
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Pulmonary acini exhibit complex changes during postnatal rat lung development
David Haberthür1, Eveline Yao1, Sébastien F Barré1
1Institute of Anatomy, University of Bern, Bern, Switzerland.
Plos One
|November 8, 2021
Summary
Pulmonary acini, the lung's gas-exchange units, grow significantly and become more uniform in size during development. This homogenization optimizes lung function and ventilation in adult rats.
Area of Science:
- Pulmonary research
- Developmental biology
- Medical imaging
Background:
- Pulmonary acini are the functional units of the lung responsible for gas exchange.
- Identifying individual acini in microscopic lung sections is challenging due to technical limitations.
Purpose of the Study:
- To overcome limitations in visualizing individual pulmonary acini.
- To characterize the developmental changes in acinar volume and alveolar number in rat lungs.
Main Methods:
- High-resolution 3D imaging of rat lungs at multiple postnatal stages (P4, P10, P21, P60) using synchrotron X-ray microtomography.
- Segmentation of individual pulmonary acini by airway closure at the conducting-to-gas-exchanging transition.
- Stereological assessment of acinar volume and alveolar count for developmental analysis.
Main Results:
- Mean acinar volume increased 23-fold from postnatal day 4 to day 60.
- The size distribution of pulmonary acini significantly homogenized, with the ratio of the largest to smallest acini decreasing from 27.26 to 4.07.
- The coefficient of variation for acinar volume decreased from 1.26 to 0.49 during lung maturation.
Conclusions:
- Pulmonary acini undergo substantial growth and size homogenization during postnatal development.
- Homogenization of acinar size suggests optimization of the gas-exchange region and potentially more uniform lung ventilation in adult rats.
- Early variations in acinar size may indicate non-uniform distribution within the developing lung.
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