The mechanisms and control of bronchial mucous cell hyperplasia.

The studies presented here describe the involvement of cell proliferation, differentiation and transformation in the epithelial mucous cell increase observed in the airways of experimental animals exposed to tobacco smoke (TS) for 14 days: the inhibitory effect of concurrent administration by injection of non-steroidal and steroidal anti-inflammatory drugs is also presented. In response to T.S. mucous cells arise mainly by self-replication and transformation of existing serous (secretory) cells while the production of ciliated cells appears to be mainly by differentiation of basal cells. Indomethacin inhibits the T.S.-induced mucous cell increase in a dose related way, the extent of which is dependent on the initial degree of response to T.S. and the airway level studied. The steroids dexamethasone, prednisolone and hydrocortisone, whilst effective in their inhibition gave no particular advantage over and above that seen with Indomethacin.