LEUKOTRIENES C4 AND D4 INDUCE PROSTAGLANDIN AND THROMBOXANE RELEASE FROM RAT PERITONEAL MACROPHAGES

Abstract

The present study examined the effect of leukotrienes C₄ and D₄, the products of the 5′ lipoxygenase pathway on prostaglandins and thromboxane release from rat peritoneal macrophages. Incubation of rat peritoneal macrophages with leukotrienes C₄ and D₄ enhanced the release of prostaglandin E₂ (PGE₂), 6-keto PGF_1α and thromboxane B₂ (TxB₂) in a dose-dependent manner. The increase of PGE₂ was more pronounced than that of 6-keto-PGF_1α and TxB₂. Lipopolysaccharide, a known stimulator of these cells elicited a similar pattern of increase of the arachidonate metabolites assayed. These results suggest that leukotrienes C₄ and D₄ are potential activators of macrophages. Since leukotrienes C₄ and D₄ are produced by these cells, it is suggested that endogenous leukotrienes may be involved in activation of macrophages.