Goblet cell glycoprotein and tracheal gland hypertrophy in rat airways: the effect of tobacco smoke with or without the anti-inflammatory agent phenylmethyloxadiazole.

A quantitative analysis has been made of tracheal gland size and of histochemical changes occurring in goblet cells of the respiratory epithelium, in rats exposed either to tobacco smoke alone or to tobacco smoke with phenylmethyloxadiazole (PMO). Exposure to tobacco smoke alone causes an increase in goblet cell number with a shift from the production of neutral to acid glycoprotein, mainly sialidase resistant sialomucin but some sialidase sensitive sialomucin and sulphomucin. Acid glycoprotein, and each of its types, appears first at the cell apex. The addition of PMO to the tobacco protects against the increase in goblet cell number but gives no protection against the shift from neutral to acid glycoprotein and causes a larger secretory mass within the goblet cell. In the tracheal gland exposure to smoke from either tobacco alone or tobacco with PMO causes a significant increase in cell size and acinar diameter and a lesser increase in lumen diameter. There is also an increase in the thickness of the gland and its depth. Each of these gland changes is more pronounced in those animals receiving PMO with the tobacco.