Release of leukotriene B4 from rat Kupffer cells

Abstract In order to examine the production of leukotriene B 4 (LTB 4 ) from Kupffer cells, Kupffer cells isolated from the normal rat liver were incubated with calcium ionophore A23187, opsonized zymosan, or platelet activating factor (PAF), and the amount of LTB 4 in the culture supernatant was determined by the combined technique of reverse-phase high-performance liquid chromatography and radioimmunoassay. As a result, when activated in vitro with calcium ionophore A23187, Kupffer cells generated LTB 4 . When Kupffer cells were stimulated with calcium ionophore after 10-min preincubation with AA861, a selective 5-lipoxygenase inhibitor, the release of LTB 4 from Kupffer cells was markedly suppressed. PAF, which is a phospholipid mediator having a wide spectrum of biological activities, significantly enhanced the release of LTB 4 from Kupffer cells stimulated with calcium ionophore or opsonized zymosan. Even when the Kupffer cell were not stimulated with calcium ionophore or opsonized zymosan, LTB 4 production was significantly increased by PAF. Thus, our studies indicate that Kupffer cells could generate LTB 4 as well as polymorphonuclear leukocytes and macrophages. In addition, it is suggested that Kupffer cells may be able to modify inflammatory and immunological events in the liver tissue by the release of LTB 4 .