Morphometric analysis of the non-epithelial areas of mouse bronchioles through the normal aging process.

Aging is associated with changes in the structure and function of the lung that may increase susceptibility to chronic lung diseases. The aim of this study was the morphometric assessment of the non-epithelial areas of the bronchioles of mouse through the normal aging process. Lungs from CD1 mice at the age of 2, 6, 12, 18, or 24 months were fixed in neutral-buffered formalin and paraffin-embedded. Sections were cut, stained with Masson trichrome, and examined using a light microscope. High-resolution color images were captured using a camera linked to image analysis software to measure areas and lengths. We observed in the bronchioles through the aging process an increase of the total area, an increase of the lumen area, and a decrease of the wall area. In conclusion, our results revealed structural changes in the bronchioles of mouse through the normal aging process. These alterations are likely to contribute to development of chronic lung diseases.