The availability of alpha- and beta-adrenergic receptors in murine epidermal cells was revealed by means of adrenomimetic and adrenolitic drugs, these receptors having direct influence on the cell division in epidermis. The simultaneous as well as independent stimulation of alpha- and beta-receptors by mesation (phenylephrine) and isadrin (isoproterenol), respectively, markedly inhibits the transition of epidermal cells from interphase into mitosis. The effect is observable in 2 hours. Thus, the interaction of adrenaline with adrenergic receptors in epidermis may be considered as a way by which this hormone may control the mitotic activity.