Translocation of HL-60 cell 5-lipoxygenase. Inhibition of A23187- or N-formyl-methionyl-leucyl-phenylalanine-induced translocation by indole and quinoline leukotriene synthesis inhibitors

We have demonstrated translocation of HL-60 cell 5-lipoxygenase to a membrane compartment in response to both the calcium ionophore A23187 and the receptor-mediated stimulus, N-formyl-methionyl-leucyl-phenylalanine (fMLP). In addition, we have shown inhibition of A23187- and fMLP-induced 5-lipoxygenase translocation by an indole and a quinoline leukotriene synthesis inhibitor, MK-886 and L-674,573, respectively. Selectivity of inhibition of 5-lipoxygenase translocation in both fMLP- or A23187-challenged cells is shown using the indole L-583,916 and quinoline L-671,480, which neither inhibit leukotriene synthesis nor inhibit 5-lipoxygenase translocation. The present study in HL-60 cells is the first demonstration of the selective inhibition of 5-lipoxygenase translocation by quinoline leukotriene synthesis inhibitors, exemplified by L-674,573. Also described here is the first demonstration of 5-lipoxygenase translocation and inhibition in response to a stimulus other than A23187, namely the receptor-mediated stimulus, fMLP.