Effect of PAF inhalation on the non-specific bronchial hyperreactivity according to the severity of asthma.
- Author:
Mi Kyeong KIM
;
ou Young KIM
- Publication Type:Original Article
- MeSH:
Asthma*;
Bronchi;
Bronchial Hyperreactivity*;
Bronchoconstriction;
Eosinophils;
Inhalation*;
Methacholine Chloride;
Platelet Count
- From:Korean Journal of Allergy
1997;17(2):129-140
- CountryRepublic of Korea
- Language:Korean
-
Abstract:
PAF itself induces the non-specific bronchial hyperreactivity(NSBH) in asthma. NSBH induced by PAF is nearly as same as that by the sensitized allergen inhalation even though PAF never provokes the late asthmatic response. Usually the amount of allergen for BPT inversely correlated with the severity of asthma, but in PAF, nothing was clarified about that, yet. usually eosinophil is the main effector cell in PAF-induced NSBH. So we want to declare whether PAF inhalation affects the NSBH differently according to the severity of asthma or not in this study and eosinophil is the main effector cell in asthmatics. Single dose PAF(400microgram/microliter) inhalation challenge was done by the Cockcroft' s method but that of methacholine by Chai's method before and after PAF until NSBH returned the basal value. From that, we calculated PC20. Also we checked the eosinophil and platelet count in peripheral blood before and after PAF until those returned the baseline. All these were done in two groups, mild asthmatics and moderate asthmatics classified by the PFT and their PC20. The Bronchoconstriction started at the 3 minutes after PAF inhalation and then relieved completely 30 minutes after inhalation but in mild asthmatics bronchi constricted much more than moderate asthmatics. The fall of NSBH also persisted much longer in mild asthmatics. But the decrease in peripheral eoslnophil counts was nearly same in both groups. None of asthmatics showed the changes in platelet counts in peripheral blood. The degree of bronchoconstriction and decrease in eosinophil counts didn't have any correlation with the persistence of the NSBH. Taken together, PAF inhalation affected the NSBH inversely according to the severity of asthma in this study but eosinophil might not be the only effector cell in PAF-induced NSBH.
