Bradykinin- and chemotactic peptide fMLP-stimulated leukotriene biosynthesis in rat lungs and its inhibition by vasoactive intestinal peptide.

The release/biosynthesis of peptidoleukotrienes (pLT) from rat lung tissue was stimulated with either bradykinin (Bk) or the chemotactic peptide formyl-methionyl-leucinyl-phenylalanine (fMLP). Bk- and fMLP-induced stimulation of pLT levels was dose-related for leukotriene D4 (LTD4), E4 (LTE4) and total pLTs and was maximal when a 10 microM concentration of either peptide was used. This stimulation was partially counteracted by vasoactive intestinal peptide (VIP), in agreement with the previously reported VIP inhibition of platelet activating factor- and IgG-stimulated pLT biosynthesis.