HYDROCORTISONE INCREASES THE RESPONSIVENESS OF MAST-CELLS TO BETA-ADRENERGIC AGONISTS BY AN ACTION DISTAL TO THE BETA-ADRENORECEPTORS

  • 1 January 1979
    • journal article
    • research article
    • Vol. 60  (3) , 269-275
Abstract
Hydrocortisone in pharmacologically attainable concentrations potentiates .beta.-adrenergic-stimulated cyclic[c]AMP accumulation in rat peritoneal mast cells. Direct binding studies using 3H-dihydroalprenolol indicated no significant changes in the number of .beta.-adrenoreceptors or in the kinetics of the interaction of the radioligand with receptors after treatment of mast cells with the corticosteroid. Competition binding studies with epinephrine revealed no hydrocortisone-induced change in Kd values for this agonist. Hydrocortisone-induced stimulation of cAMP synthesis results from an effect that occurs beyond the interaction of the .beta.-adrenergic agonist with its receptor.