Mackay T W, Wallace W A, Howie S E, Brown P H, Greening A P, Church M K, Douglas N J
Department of Medicine (RIE), University of Edinburgh, UK.
Thorax. 1994 Mar;49(3):257-62. doi: 10.1136/thx.49.3.257.
Nocturnal airway narrowing is a common problem for patients with asthma but the role of inflammation in its pathogenesis is unclear. Overnight changes in airway inflammatory cell populations were studied in patients with nocturnal asthma and in control normal subjects.
Bronchoscopies were performed at 0400 hours and 1600 hours in eight healthy subjects and in 10 patients with nocturnal asthma (> 15% overnight fall in peak flow plus at least one awakening/week with asthma). The two bronchoscopies were separated by at least five days, and both the order of bronchoscopies and site of bronchoalveolar lavage (middle lobe or lingula with contralateral lower lobe bronchial biopsy) were randomised.
In the normal subjects there was no difference in cell numbers and differential cell counts in bronchoalveolar lavage fluid between 0400 and 1600 hours, but in the nocturnal asthmatic subjects both eosinophil counts (median 0.11 x 10(5) cells/ml at 0400 hours, 0.05 x 10(5) cells/ml at 1600 hours) and lymphocyte numbers (0.06 x 10(5) cells/ml at 0400 hours, 0.03 x 10(5) cells/ml at 1600 hours) increased at 0400 hours, along with an increase in eosinophil cationic protein levels in bronchoalveolar lavage fluid (3.0 micrograms/ml at 0400 hours, 2.0 micrograms/l at 1600 hours). There were no changes in cell populations in the bronchial biopsies or in alveolar macrophage production of hydrogen peroxide, GM-CSF, or TNF alpha in either normal or asthmatic subjects at 0400 and 1600 hours. There was no correlation between changes in overnight airway function and changes in cell populations in the bronchoalveolar lavage fluid.
This study confirms that there are increases in inflammatory cell populations in the airway fluid at night in asthmatic but not in normal subjects. The results have also shown a nocturnal increase in eosinophil cationic protein levels in bronchoalveolar lavage fluid, but these findings do not prove that these inflammatory changes cause nocturnal airway narrowing.
夜间气道狭窄是哮喘患者的常见问题，但其发病机制中炎症的作用尚不清楚。我们研究了夜间哮喘患者和正常对照受试者气道炎症细胞群的夜间变化。
对8名健康受试者和10名夜间哮喘患者（峰流速夜间下降>15%且每周至少因哮喘发作觉醒1次）在凌晨4点和下午4点进行支气管镜检查。两次支气管镜检查间隔至少5天，支气管镜检查顺序和支气管肺泡灌洗部位（中叶或舌叶加对侧下叶支气管活检）均随机安排。
正常受试者凌晨4点和下午4点支气管肺泡灌洗液中的细胞数量和细胞分类计数无差异，但夜间哮喘患者凌晨4点时嗜酸性粒细胞计数（中位数：凌晨4点为0.11×10⁵个细胞/毫升，下午4点为0.05×10⁵个细胞/毫升）和淋巴细胞数量（凌晨4点为0.06×10⁵个细胞/毫升，下午4点为0.03×10⁵个细胞/毫升）均增加，同时支气管肺泡灌洗液中嗜酸性粒细胞阳离子蛋白水平升高（凌晨4点为3.0微克/毫升，下午4点为2.0微克/升）。凌晨4点和下午4点时，正常或哮喘受试者的支气管活检中的细胞群以及肺泡巨噬细胞产生过氧化氢、粒细胞巨噬细胞集落刺激因子或肿瘤坏死因子α均无变化。夜间气道功能变化与支气管肺泡灌洗液中细胞群变化之间无相关性。
本研究证实哮喘患者夜间气道液中炎症细胞群增加，而正常受试者无此现象。结果还显示支气管肺泡灌洗液中嗜酸性粒细胞阳离子蛋白水平夜间升高，但这些发现并不能证明这些炎症变化会导致夜间气道狭窄。
