Abstract

The ultrastructural appearance of rat tracheal submucosal glands after exposure to tobacco smoke for up to two years is described. Within the mucous cells many of the rough endoplasmic reticulum cisternae were grossly dilated with an accumulation of amorphous, electron-lucent material. The Golgi zones were prominent, and the secretion granules often contained dense cores, and appeared to have coalesced. Histochemically, increased amounts of sulphated mucus were present in exposed rats. Serous, ciliated, and myoepithelial cells were unaffected by smoke exposure.