Abstract
2-n-Heptyl-4-hydroxyquinoline-N-oxide (KF8940), isolated from Pseudomonas methanica, was a potent and selective inhibitor of the arachidonate 5-lipoxygenase of rat basophilic leukemia (RBL-1) cells. Kinetic analysis indicated that the inhibitory mode was non competitive. The Ki value was 3.5 × 10-7 M. KF8940 also inhibited 12-lipoxygenase of bovine platelets in a noncompetitive manner, but with a Ki value of 7 × 10-5 M. lonophore A23187-stimulated SRS generation from rat peritoneal cells and antigen-stimulated SRS-A generation from sensitized rat lung were significantly inhibited by KF8940. KF8940 at a dose of 10 mg/kg (p.o.) suppressed the passive anaphylactic bronchoconstriction in guinea pigs.
