| Autor: |
Hazucha MJ, Ginsberg JF, McDonnell WF, Haak ED Jr, Pimmel RL, Salaam SA, House DE, Bromberg PA |
| Jazyk: |
angličtina |
| Zdroj: |
Journal of applied physiology: respiratory, environmental and exercise physiology [J Appl Physiol Respir Environ Exerc Physiol] 1983 Mar; Vol. 54 (3), pp. 730-9. |
| DOI: |
10.1152/jappl.1983.54.3.730 |
| Abstrakt: |
It has been reported (J. Clin. Invest. 57: 301-307, 1976) that inhalation of nitrogen dioxide (NO2) will enhance the bronchial reactivity of asthmatics. This study was designed to evaluate the respiratory effect of a 1-h exposure of normal subjects and of atopic asthmatics to 0.1 parts per million (ppm) NO2. Fifteen normal and 15 asthmatic subjects were exposed to air and to NO2 in a randomized double-blind crossover design. Exposure to either atmosphere was bracketed by bronchial inhalation challenge using aerosolized metacholine chloride solutions. Plethysmographic measurements of specific airway resistance (sRaw) and the forced random noise impedance spectrum (5-30 Hz) were obtained immediately after each methacholine dose. Following acute exposure to NO2, there was a slight but not significant increase in mean base-line sRaw in both normals and asthmatics. The overall base-line resistive properties of the respiratory system determined by forced random noise excitation were not significantly affected by NO2 inhalation either. Finally, there was no change in bronchial response to methacholine challenge in either group. These findings indicate that 0.1 ppm NO2 exposure for 1 h without exercise had no demonstrable airways effects in either young atopic asthmatics with mild disease or young normal subjects. |
| Databáze: |
MEDLINE |
| Externí odkaz: |
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