Glucocorticoid-induced vasoconstriction in human skin. An inhibitory role on phospholipase A2 activity

• The ability of topically applied betamethasone valerate to reduce erythema produced by a variety of vasodilators was assessed. The steroid significantly reduced the erythema induced by topical arachidonic acid, intradermal histamine, and compound 48/80. We postulated that the steroid reduced endogenous phospholipase activity either before or after application of the vasodilators, or both. This action may explain the mechanism of glucocorticoid-induced vasoconstriction in the skin and part of the steroids' action in acute inflammatory skin disease. (Arch Dermatol1986;122:881-883)