RESPONSES OF TRACHEAL EPITHELIUM TO STEROID HORMONES
The effects of 17(beta)-estradiol and progesterone treatment on the tracheal epithelium of the rabbit were studied in vivo and in vitro. Morphological analysis of the epithelial secretory cells by the combined Alcian blue (AB) and periodic acid Schiff (PAS) staining method revealed a significant increase in the total number of secretory cells, particularly the AB+ cells, following estrogen treatment of ovariectomized rabbits. The effects of progestrone treatment were less dramatic, only the large AB+ cells showing a significant increase with no apparent change in the total number of stained cells. When the tracheal mucosa obtained from ovariectomized control, estrogen or progesterone treated rabbits was incubated with the glycoprotein precursors, ('3)H-fucose and ('14)C-glucosamine, a significant increase in uptake of both labels was observed in the two treated groups compared to the control indicating an increase in glycoprotein synthesis in the trachea following hormone treatment.^ The pattern and specificity of uptake of ('3)H-17(beta)-estradiol by the tracheal mucosa was studied in an effort to identify its mode of action. The labeled steroid was shown to be taken up by rabbit tracheal tissue in vivo and in vitro. The amount of uptake in vivo was determined to be intermediate to that shown by a target and a non-target organ. The retention of the steroid by the tracheal tissue even 4.5 hours after the single iv injection indicated some affinity. The unexpectedly high uptake of the steroid in vitro and the fact that excess unlabeled ligand only partially suppressed binding suggest a large percentage of non-specific binding. Receptor binding studies, though not conclusive, indicate the presence of some specific estradiol receptors in the cytosol of the rabbit trachea.^ The effects of estrogen and progesterone on tracheal epithelium were studied further in tissue culture. Estrogen treatment (10('-5)M) of the tracheal explant cultures seemed to have no effect on the gross morphology of the epithelium. Progesterone (10('-5)M), on the other hand, appeared to disrupt the structural integrity of the explant epithelium causing vacuolation and rounding up of cells and often resulting in complete denuding. This toxic effect was not counteracted by the addition of estrogen to the medium. Estrogen treatment was shown to cause an increase in the number of ciliated cells in the outgrowth after 2 weeks in culture indicating an influence on the differentiation of these cells and probably of the secretory cells also. . . . (Author's abstract exceeds stipulated maximum length. Discontinued here with permission of author.) UMI ^
CHOJNOWSKI, BARBARA, "RESPONSES OF TRACHEAL EPITHELIUM TO STEROID HORMONES" (1983). ETD Collection for Fordham University. AAI8323517.