Background We previously reported that inhaled acetaldehyde, a metabolite of ethanol atid a maiti factor in alcohol-induced asthma, causes bronchial hyper-responsiveness (BHR) in asthmatics. However, the mechanisms are unclear.
Objective The purpose of this study was to investigate a role of a peptide leukotriene (LT) in acetaldehyde-induced BHR.
Methods Effects of LT antagonists, ONO-1078 (O.l-l.Omg/kg) and ICI-198, 615 (0.03–0.3 mg/kg), on acetaldehyde-induced bronchoconstriction and BHR to inhaled methacho-line were examined using a modified Konzett-Rössler method in guinea pigs.
Results Aeetaldehyde at 0.8mg/ml, which failed to induce significant changes in Pao (pressure at the airway opening), enhanced an increase in Pao induced by subsequent inhalations of ascending doses (50–200 μg/ml) of methacholine. suggesting a potentiating effect of acetaldehyde oti bronchial responsiveness. Although ONO-1078 had no inhibitory effect on bronchoconstriction caused by ascending doses (5.0–20 mg/ml) of acetaldehyde, ONO-1078 and ICI-198, 615 reduced the acetaldehyde-induced BHR.
Conclusion Acetaldehyde causes BHR via LT release in guinea-pigs.