Modulation of substance P-induced bronchoconstriction by lipoxygenase metabolites.

In anaesthetized, mechanically ventilated guinea-pigs, substance P induces a bronchoconstrictor response comprising increases in airway resistance and decreases in dynamic compliance. Eicosatetraynoic acid (ETYA, 20 mg kg-1 i.v.) or BW755c (20 mg kg-1 i.v.) potentiated the substance P-induced bronchoconstriction. Neither indomethacin (1 or 5 mg kg-1 i.v.) nor aspirin (20 mg kg-1 i.v.) significantly altered the potency of substance P on bronchomotor responses. These observations are consistent with the existence of a bronchodilator lipoxygenase metabolite(s).