Glucocorticoid receptors of normal human epidermis.

Epidermal cytosol of adult humans can bind dexamethasone, and this binding resembles that by glucocorticoid receptors of other tissues as judged by 4 criteria: affinity of binding, specificity of binding, molecular size of receptor-steroid complexes, and ability of these complexes to bind to nuclei. For demonstration of these receptors, epidermis can be separated by trypsinization but only after preliminary incubation of the skin with molybdate ion, which prevents inactivation of receptors when heated to 22 degree C. The presence of these receptors suggest that glucocorticoids may act directly on the epidermis. Five glucocorticoids that are used topically all displaced 3H-dexamethasone from the receptor in vitro but the affinity of this binding correlates imperfectly with the potency of the steroids when used in vivo.