Effect of short-term, low-level nitrogen dioxide exposure on bronchial sensitivity of asthmatic patients.
Effect of short-term, low-level nitrogen dioxide exposure on bronchial sensitivity of asthmatic patients.
复制标题
短期低水平二氧化氮暴露对哮喘患者支气管敏感性的影响。
DOI：
--
复制
发表时间：
1976
影响因子：
15.9
通讯作者：
J. Charpin
中科院分区：
文献类型：
--
作者：
J. Orehek;J. P. Massari;P. Gayrard;C. Grimaud;J. Charpin
我们的目的是确定暴露于实际浓度的二氧化氮 (NO2) 是否会增加哮喘患者对支气管收缩剂的敏感性。我们建立了 20 名哮喘患者雾化卡巴胆碱后比气道阻力 (SRaw) 变化的剂量反应曲线，每人在暴露室中呼吸 1 小时，一次呼吸未污染的空气，另一次呼吸 0.1 ppm NO2：以单盲方式随机暴露于未污染空气和低水平 NO2 的顺序。 NO2 使 13 名受试者的初始 SRaw 略有但显着增加，并增强了卡巴胆碱的支气管收缩作用：曲线向左移动，使初始 SRaw 增加两倍的卡巴胆碱平均剂量从 0.66 mg 降至 0.36 mg（P 小于 0.001）。相比之下，在七名受试者中，NO2 既没有改变最初的 SRaw，也没有改变卡巴胆碱的支气管收缩作用。 20 名受试者中有 4 名暴露于较高浓度的二氧化氮 (0.2 ppm)，结果各不相同。 NO2 对卡巴胆碱支气管收缩反应的增强作用与受试对象的任何身体或临床特征无关。尽管 NO2 作用的机制仍存在争议，但目前的结果表明，极低水平的 NO2 会对某些哮喘患者产生不利影响。
Our purpose was to determine whether exposure to a realistic concentration of nitrogen dioxide (NO2) could increase the bronchial sensitivity of asthmatic patients to bronchoconstrictor agents. We established dose-response curves for changes in specific airway resistance (SRaw) in response to aerosolized carbachol in 20 asthmatics after each had spent 1 h in an exposure chamber breathing on one occasion unpolluted air and on a separate occasion 0.1 ppm NO2: sequence of exposures to unpolluted air and to low levels of NO2 were randomized in a single-blind fashion. NO2 induced a slight but significant increase in initial SRaw and enhanced the bronchoconstrictor effect of carbachol in 13 subjects: curves were shifted to the left and the mean dose of carbachol producing a twofold increase in initial SRaw was decreased from 0.66 mg to 0.36 mg (P less than 0.001). In contrast, NO2 neither modified the initial SRaw nor the bronchoconstrictor effect of carbachol in seven subjects. In 4 out of the 20 subjects, exposure to a higher concentration of NO2 (0.2 ppm) yielded variable results. Potentiation of the carbachol bronchoconstrictor response by NO2 could not be related to any physical or clinical characteristics of the subjects tested. Although the mechanisms underlying the NO2 effect remain controversial, the present results demonstrate that very low levels of NO2 can adversely affect some asthmatics.