Nightingale J A, Rogers D F, Chung K F, Barnes P J
Thoracic Medicine, National Heart and Lung Institute, Imperial College, London, United Kingdom.
Am J Respir Crit Care Med. 2000 Feb;161(2 Pt 1):479-86. doi: 10.1164/ajrccm.161.2.9905031.
Inhalation of ozone in normal subjects causes a neutrophilic inflammatory response in the airways. Pretreatment with inhaled corticosteroids reduces the inflammatory response to inhaled ozone in dogs. We undertook a double-blind, randomized, placebo-controlled, crossover study to investigate the effects of 2 wk of treatment with inhaled budesonide 800 microg twice daily or placebo prior to ozone exposure in humans. Fifteen (six male; mean age, 31.1 +/- 2.1 yr) healthy nonsmokers were exposed to 400 parts per billion (ppb) ozone for 2 h with intermittent exercise. Spirometry, exhaled carbon monoxide (CO) and nitric oxide (NO) levels, measurement of methacholine reactivity, and collection of exhaled air condensate and induced sputum samples were performed at baseline, preexposure, and at intervals up to 24 h postexposure. Ozone exposure led to significant decreases in spirometry and increased methacholine reactivity and sputum neutrophils and myeloperoxidase (MPO). There were no changes in exhaled NO and CO levels, or exhaled breath nitrite after ozone exposure. There were no differences in any of the parameters after treatment with budesonide compared with placebo, and no differences in the response to ozone between treatment groups. We conclude that a high dose of inhaled corticosteroid does not protect against the effects of ozone exposure in normal subjects.
正常受试者吸入臭氧会导致气道出现嗜中性粒细胞炎症反应。吸入性皮质类固醇预处理可减轻犬类对吸入臭氧的炎症反应。我们进行了一项双盲、随机、安慰剂对照、交叉研究，以调查在人类暴露于臭氧之前，每天两次吸入800微克布地奈德或安慰剂治疗2周的效果。15名（6名男性；平均年龄31.1±2.1岁）健康非吸烟者在间歇性运动的情况下暴露于400 ppb的臭氧中2小时。在基线、暴露前以及暴露后长达24小时的间隔时间进行肺功能测定、呼出一氧化碳（CO）和一氧化氮（NO）水平测定、乙酰甲胆碱反应性测量以及收集呼出空气冷凝物和诱导痰样本。臭氧暴露导致肺功能测定值显著下降，乙酰甲胆碱反应性、痰液嗜中性粒细胞和髓过氧化物酶（MPO）增加。臭氧暴露后呼出NO和CO水平以及呼出气体亚硝酸盐没有变化。与安慰剂相比，布地奈德治疗后任何参数均无差异，治疗组之间对臭氧的反应也无差异。我们得出结论，高剂量吸入性皮质类固醇不能保护正常受试者免受臭氧暴露的影响。
