Effect of PAF-acether inhalation on nonspecific bronchial reactivity and adrenergic response in normal and asthmatic subjects.
Bronchial hyperreactivity, although recognized as a hallmark of asthma, is not totally understood. Mast cell-derived mediators, including histamine, have been shown to cause immediate bronchoconstriction, but until recently, no single mediator has been shown to induce prolonged changes in airway reactivity. Recent reports indicate PAF-acether (PAF) can induce increased nonspecific bronchial reactivity in normal subjects but not in asthmatics. We sought to elucidate the role of PAF in airway hyperreactivity by comparing the effect of inhaled PAF on methacholine and isoproterenol airway responsiveness in six nonasthmatic and six asthmatic subjects. Neither nonspecific airway reactivity nor isoproterenol responsiveness was changed following PAF inhalation in the nonasthmatic subjects in the six days following PAF. Asthmatics had increased airway responsiveness to methacholine at two hours post-PAF, which did not persist. Responsiveness to isoproterenol did not change in the asthmatic subjects. Additional evaluation of the role of PAF in causing changes in airway reactivity is warranted.
Hopp
R J
RJ
Allergic Disease Center, Creighton University School of Medicine, Omaha 68178.
Bewtra
A K
AK
Nabe
M
M
Agrawal
D K
DK
Townley
R G
RG
D000328:Adult; D001249:Asthma / Q000097:blood / Q000503:physiopathology*; D001985:Bronchial Provocation Tests; D016084:Bronchoconstriction / Q000187:drug effects*; D005260:Female; D005540:Forced Expiratory Flow Rates / Q000187:drug effects; D005541:Forced Expiratory Volume / Q000187:drug effects; D006801:Humans; D007545:Isoproterenol / Q000494:pharmacology*; D007958:Leukocyte Count / Q000187:drug effects; D008297:Male; D016210:Methacholine Chloride; D010972:Platelet Activating Factor / Q000494:pharmacology*
D010972:Platelet Activating Factor; D016210:Methacholine Chloride; D007545:Isoproterenol