Effect of beta adrenergic stimulation and blockade on immediate hypersensitivity skin test reactions

The effects of isoproterenol (a β-adrenergic stimulating agent) and propranolol (a β-adrenergic blocking agent) were studied on immediate hypersensitivity skin test reactions in 15 atopic subjects. Forearm skin of these subjects was pretreated with these agents by local iontophoretic application and compared to areas locally pretreated with saline or diphenhydramine hydrochloride. Following pretreatment of skin, scratch or intradermal tests were performed with the most reactive antigen for each patient. A significant increase of skin reactivity occurred in areas of skin pretreated with propranolol. A significant decrease in reactivity followed pretreatment with isoproterenol. Thus the iontophoresis of β-adrenergic agents can alter the immediate hypersensitivity skin test reactions of atopic patients. This alteration is consistent with a modification of the local synthesis of cyclic adenosine monophosphate (CAMP) induced by these pharmacologic agents. It is not clear whether this presumed alteration in CAMP is exerting its effect on mediator release from dermal mast cells or directly on the dermal blood vessels or both.