Leukotrienes C4 and D4 induce prostaglandin and thromboxane release from rat peritoneal macrophages.

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 PGF1 alpha and thromboxane B2 (TxB2) in a dose-dependent manner. The increase of PGE2 was more pronounced than that of 6-keto-PGF1 alpha 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.