Am. J. Respir. Crit. Care Med., Vol 152, No. 2, Aug 1995, 456-460.
Repeated inhalation challenge with exogenous and endogenous histamine released by acetaldehyde inhalation in asthmatic patients
S Myou, M Fujimura, Y Kamio, T Bando, Y Nakatsumi and T Matsuda
Third Department of Internal Medicine, Kanazawa University School of Medicine, Japan.
We previously reported that inhaled acetaldehyde, a metabolite of ethanol
and a main factor in alcohol-induced asthma, causes bronchoconstriction
indirectly through endogenously released histamine in asthmatic subjects.
No study has examined the difference between tachyphylaxis in response to
endogenous as opposed to exogenous histamine. Therefore, we examined
tachyphylaxis occurring in response to repeated inhalation of histamine or
acetaldehyde in nine asthmatic subjects. The mean acetaldehyde
concentration causing a 20% decrease in FEV1 increased significantly from
18.4 (geometric standard error of the mean (GSEM = 0.14) to 45.2 (GSEM =
0.14) mg/ml over a period of 1 h (p < 0.002), whereas the mean histamine
concentrations causing a 20% decrease in FEV1 were identical. No
correlations were observed between the change in bronchial responsiveness
to each solution and the change in baseline FEV1. These results suggest
that tachyphylaxis in response to histamine is observed only when the
latter is released endogenously. We believe that this is the first report
suggesting tachyphylaxis caused by endogenous histamine.
