[Effects of antiallergic agents on polymorphonuclear leukocytes. The inhibition of arachidonic acid release and superoxide production].
The aim of this study was to examine the effects of antiallergic agents on the functions of polymorphonuclear leukocytes (PMNs) in terms of its arachidonic acid release and superoxide-anion generation. The stimulations of arachidonic acid release by formyl-methionyl-leucyl-phenylalanine (FMLP) were effectively diminished by 20 microM of azelastine as well as clemastine. Challenges of 20 microM and 50 microM of these agents inhibited approximately 50% and 100% of the arachidonic acid release, respectively. On the contrary, inhibitions of over 50% were not caused by cromoglycate, chlorpheniramine and diphenhydramine at concentrations up to 50 microM. The potency of the above examined drugs on the superoxide generations from PMNs were similar to the effects of arachidonic acid release. Ketotifen, however, showed intermediate effects indicating that a challenge of 50 microM ketotifen inhibited approximately 50% of the arachidonic acid release without having an effect on the superoxide generation. These experimental observations suggested that one of the important roles of the antiallergic agents including azelastine (known as a chemical mediator release inhibitor) and clemastine (known as a histamine H1 receptor antagonist) could be an inhibition of the first step of the arachidonic acid cascade.
D000818:Animals; D001095:Arachidonic Acids / Q000378:metabolism*; D006634:Histamine H1 Antagonists / Q000494:pharmacology*; D009240:N-Formylmethionine Leucyl-Phenylalanine / Q000494:pharmacology; D009504:Neutrophils / Q000187:drug effects* / Q000378:metabolism; D011817:Rabbits; D013481:Superoxides / Q000378:metabolism*
D001095:Arachidonic Acids; D006634:Histamine H1 Antagonists; D013481:Superoxides; D009240:N-Formylmethionine Leucyl-Phenylalanine