Mohsenin V
John B. Pierce Foundation Laboratory, New Haven, Connecticut 06519.
J Toxicol Environ Health. 1987;22(4):371-80. doi: 10.1080/15287398709531080.
Nitrogen dioxide is a common indoor air pollutant. In order to characterize the respiratory responses to this gas, 10 asthmatics (mean age +/- SD = 30 +/- 8 yrs) were exposed to air and 0.5 ppm NO2 gas for 1 h in a 30-m3 environmental chamber on different days in a double-blind randomized fashion. The forced vital capacity, (VC), functional residual capacity, forced expiratory volume in 1 s, partial expiratory flow at 40% VC (Vp 40), and specific airway conductance were measured before and after exposure. Airway reactivity to methacholine inhalation was determined after each exposure. The dose of methacholine in milligrams per milliliter to cause a 40% decrease in Vp 40 was measured. None of the subjects reported any significant symptoms after exposure. Significant potentiation of airway reactivity was noted after NO2 exposure in asthmatic subjects as a group [PD40(AIR) = 9.2 +/- SD 15.0 versus PD40(NO2) = 4.6 +/- SD 8.2 mg/ml, p = 0.042]. No significant changes were noted in other lung functions after NO2 exposure. These findings indicate that asthmatics exposed to 0.5 ppm NO2 develop heightened airway reactivity.
二氧化氮是一种常见的室内空气污染物。为了描述对这种气体的呼吸反应特征，10名哮喘患者（平均年龄±标准差=30±8岁）在一个30立方米的环境舱内，以双盲随机方式在不同日期分别暴露于空气和0.5 ppm的二氧化氮气体中1小时。在暴露前后测量用力肺活量（VC）、功能残气量、1秒用力呼气量、40%肺活量时的部分呼气流量（Vp 40）和比气道传导率。每次暴露后测定对吸入乙酰甲胆碱的气道反应性。测量使Vp 40降低40%的每毫升毫克数的乙酰甲胆碱剂量。暴露后没有受试者报告任何明显症状。作为一个群体，哮喘患者在暴露于二氧化氮后气道反应性有显著增强[40%降低剂量（空气）=9.2±标准差15.0与40%降低剂量（二氧化氮）=4.6±标准差8.2毫克/毫升，p = 0.042]。暴露于二氧化氮后其他肺功能没有显著变化。这些发现表明，暴露于0.5 ppm二氧化氮的哮喘患者气道反应性增强。
