Differential response in the male and female tracheal epithelium following exposure to tobacco smoke.

Histochemical quantification of goblet cells and measurements of the epithelial thickness were made in the trachea of male and female rats exposed to fresh whole tobacco smoke for 30 consecutive days. Exposure to tobacco smoke resulted in an increase in the total goblet cell count in both sexes, with the female rats differentially responding to a greater degree than the male rats. There was a shift from PAS-positive to alcian blue-positive goblet cells, an increase in the number of both "large" and "small" goblet cells, and an increase in the epithelial thickness. PAS-positive "small" cells, the major glycoprotein-reactive cell in the rat tracheal epithelium, increased in the female rats but showed no increase in the male rats. On the other hand, male rats contained a substantially higher proportion of alcian blue-positive cells than did female rats, both before and after exposure to the smoke. The significance of these observations in relation to the prevalence of chronic bronchitis in human smokers is discussed.