Pharmacological effect of KC-404 on leukotriene release from human leukocytes induced by ionophore A23187.

Release of leukotriene (LT) B4, LTC4 and histamine from human peripheral mixed leukocytes stimulated with calcium ionophore A23187 was evaluated. The amounts of LTB4 and LTC4 in supernatants were analyzed by high performance liquid chromatography and histamine was measured by an automated fluorometric technique. A time-course study demonstrated the characteristic patterns of the release of these mediators. LTB4 and LTC4 were more slowly released than histamine and the release of these LTs was inhibited by KC-404, a novel anti-asthmatic drug which has no effect on histamine release.