Inhibitions of Metabolic Responses of Polymorphonuclear Leukocytes by Antiallergic Drugs

Abstract

Sites of the inhibitory actions of antiallergic and antihistaminic drugs on polymorphonuclear leukocytes were examined by means of measurements of arachidonic acid release, superoxide anion generation and changes in membrane potential. The results obtained in this study were as follows. (i) Azelastine, an antiallergic drug, inhibited arachidonic acid release as well as superoxide generation. However, high concentrations of azelastine diminished the charge of the cells. (ii) Clemastine, used as an antihistamine, was as effective as azelastine on the metabolic bursts of leukocytes, including changes of membrane potential in leukocytes. (iii) The selective inhibition of arachidonic acid release was achieved by ketotifen without appreciable effect on superoxide generation. The relationship among the changes of membrane potential, superoxide generation and arachidonic acid release is discussed.