Lung - Metaplasia, Squamous - Gallery

Lung, Alveolus - Metaplasia, Squamous in a female Harlan Sprague-Dawley rat from a subchronic study. The normal alveolar epithelium has been replaced by squamous epithelium.

Lung, Alveolus - Metaplasia, Squamous in a female Harlan Sprague-Dawley rat from a subchronic study (higher magnification of Figure 1). The metaplastic epithelium matures normally from basal cells to squamous epithelial cells.

Lung, Alveolus - Metaplasia, Squamous in a female Harlan Sprague-Dawley rat from a chronic study. The normal alveolar epithelium has been replaced by squamous epithelium, which can be identified by the lakes of eosinophilic keratin (arrows).

Lung, Alveolus - Metaplasia, Squamous in a female Harlan Sprague-Dawley rat from a chronic study (higher magnification of Figure 3). The metaplastic epithelium is keratinized; there is also hyperplasia of the alveolar epithelium.

Lung, Bronchiole - Metaplasia, Squamous in a male F344/N rat from an acute study. The normal bronchiolar epithelium has been replaced by squamous epithelium adjacent to an ulcer.

Lung, Bronchus - Metaplasia, Squamous in a male F344/N rat from a subchronic study. The normal bronchiolar epithelium at the bifurcation of an airway has been replaced by squamous epithelium (arrow).