EPINEPHRINE PROMOTES GROWTH AND DIFFERENTIATION OF HUMAN TRACHEAL GLAND-CELLS IN CULTURE

Submucosal gland cells isolated from human tracheas by enzymatic diges tion and cultured in the absence or presence of epinephrine (E) were u sed to investigate the possible action of this catecholamine on the ph ysiology of the gland secretory cells issued from the human trachea. A 3 x 10(-6) M concentration of E shortens the doubling time of growth and increases the cells' confluency rate. On the other hand, E appears to induce cell polarity in terms of differential secretion apically v ersus basolaterally. Furthermore, when human tracheal gland cells are cultured in the presence of E, a maximal cell stimulability by differe nt agonists occurs from 8 days after confluency and then remains ident ical for 10 days, allowing us to compare the action of different adren ergic and cholinergic agonists on the proteinase bronchial inhibitor a nd the radiolabeled glycoconjugate secretion. As previously described, secretions of bronchial inhibitor and high molecular weight glycoconj ugates were stimulated both by alpha- and beta-adrenergic and by choli nergic agonists but at a much higher rate when cells were cultured in the presence of E. These results indicate that E improves cultured hum an tracheal glandular cell growth and differentiation in that it incre ases their polarity and their ability to respond to adrenergic and cho linergic agonists.