Evaluation of the Number of Alveolar Attachments through the Normal Aging Process in the Lung of CD1 Mouse

Aging has effects on lung structure and function, which may have a synergistic effect with the pathophysiology of some lung diseases to worsen lung function and diseases manifestations in aging patients. Alveolar attachments refer to the connections of the septum of the alveolar walls with the outer walls of the non-respiratory bronchioles and are important because they transmit the elastic load provided by the parenchyma to the airways. We evaluate the number of alveolar attachments through normal aging in CD1 mice. Hematoxylin and eosin-stained paraffin-embedded sections of lungs from CD1 mice aged 2, 6, 12, 18, or 24 months were examined under a light microscope. The statistical analysis showed that the number of alveolar attachments in mice at 6, 12, 18, and 24 months was significantly lower than in mice at 2 months of age. These findings may help to better understand the alterations in lung histology that promote the susceptibility of aging people to chronic diseases of the respiratory system.