Catecholamines and cyclic AMP in allergic and exercise induced asthma of childhood
โ Scribed by D. Reinhardt; M. Nagel; E. A. Stemmann; F. Wegner
- Publisher
- Springer
- Year
- 1980
- Tongue
- English
- Weight
- 465 KB
- Volume
- 134
- Category
- Article
- ISSN
- 0340-6997
No coin nor oath required. For personal study only.
โฆ Synopsis
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.
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## Abstract Morphine (10 ฮผM) blocked noradrenalineโstimulated cyclic AMP production in slices of cerebral cortex from normal rats but not in slices from rats pretreated with 6โhydroxydopamine (6โOHDA). In contrast, morphine failed to prevent noradrenalineโstimulated cyclic AMP production in mouse c