ISSN:
1432-1076
Keywords:
Exercise induced asthma (EIA)
;
Catecholamines
;
Cyclic AMP
;
a-Adrenergic blockade
;
Allergic asthma
Source:
Springer Online Journal Archives 1860-2000
Topics:
Medicine
Notes:
Abstract In order to provoke exercise induced asthma (EIA) a test which involved running for 7 min was performed with 21 asthmatic children. Eleven children not only developed a highly significant increase in airway resistance (Rt), but showed also a 4-fold increase in plasma noradrenaline (NA) levels. In 10 children who did not develop EIA only a 1.5-fold increase of NA could be observed. Following exercise cyclic AMP showed an identical increase in both groups studied, whereas adrenaline levels remained uninfluenced. Tests carried out after administration of phentolamine by inhalation showed a significant inhibition of post-exercise bronchoconstriction. It is concluded that EIA originates from a-receptor stimulation which is mediated by excessive noradrenaline release. However, since disodium cromoglycate—which does not act via adrenergic mechanisms—also protected against EIA, other factors should be involved. In 5 children with allergic asthma, asthmatic attacks were accompanied by a significant decrease in cAMP, whereas noradrenaline levels remained uninfluenced. Thus, evidence appears that both types of asthma result from different autonomic dysfunctions.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00442402
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