Effect of fenoterol on immunological release of leukotrienes and histamine from human lung in vitro: Selective antagonism by β-adrenoceptor antagonists

Abstract

The inhibitory effects of fenoterol, a β 2-adrenoceptor agonist, on the release of SRS-A leukotrienes and histamine from chopped human lung tissue were measured and selective β-adrenoceptor antagonists used to investigate the nature of the receptors involved. Fenoterol 0.01−1.0 μM inhibited the antigen-induced release of SRS-A and histamine, but not the release induced by the calcium ionophore A23187. Propranolol 0.1 and 1.0 μM and butoxamine 10 and 100 μM significantly antagonized the effects of fenoterol 0.1 μM on SRS-A and histamine at concentrations which affect β 2-adrenoceptors, while atenolol 0.1 to 10 μM showed no antagonism at concentrations which affect β 1-adrenoceptors. These results suggest that adrenoceptors in human lung which modulate the immunological release of SRS-A leukotrienes are of the β 2-subtype as for histamine release.