O'Byrne P M, Walters E H, Gold B D, Aizawa H A, Fabbri L M, Alpert S E, Nadel J A, Holtzman M J
Am Rev Respir Dis. 1984 Aug;130(2):214-9. doi: 10.1164/arrd.1984.130.2.214.
We studied whether ozone-induced hyperresponsiveness could be inhibited by neutrophil depletion in dogs. Responsiveness was assessed with dose-response curves of acetylcholine aerosol versus pulmonary resistance; depletion was assessed by counting neutrophils in venous blood and in biopsies of the airway epithelium. Responsiveness and neutrophil numbers were determined 5 days and 1 day before ozone and 1 h after ozone (3.0 ppm, 2 h) in 6 untreated dogs and in 6 dogs treated with hydroxyurea (200 mg/kg daily for 5 days starting 5 days before ozone). In untreated dogs, responsiveness and neutrophil numbers 5 days and 1 day before ozone did not change, but responsiveness and epithelial neutrophils increased markedly after ozone. In treated dogs, circulating neutrophils decreased from 8.9 +/- 2.2 to 0.6 +/- 0.01 X 10(3) per mm3 (mean +/- SEM), and responsiveness before ozone did not change. Furthermore, increases in responsiveness and epithelial neutrophils did not occur after ozone. Six wk after stopping hydroxyurea, responsiveness and epithelial neutrophils increased markedly after ozone. The results suggest that ozone-induced hyperresponsiveness may depend on the mobilization of neutrophils into the airways.
我们研究了犬中性粒细胞耗竭是否能抑制臭氧诱导的高反应性。通过乙酰胆碱气雾剂与肺阻力的剂量反应曲线评估反应性；通过计数静脉血和气道上皮活检组织中的中性粒细胞来评估耗竭情况。在6只未治疗的犬和6只经羟基脲治疗的犬（在臭氧暴露前5天开始，每天200mg/kg，共5天）中，于臭氧暴露前5天和1天以及臭氧暴露后1小时（3.0ppm，2小时）测定反应性和中性粒细胞数量。在未治疗的犬中，臭氧暴露前5天和1天的反应性和中性粒细胞数量未发生变化，但臭氧暴露后反应性和上皮中性粒细胞显著增加。在经治疗的犬中，循环中性粒细胞从每立方毫米8.9±2.2降至0.6±0.01×10³，臭氧暴露前的反应性未改变。此外，臭氧暴露后反应性和上皮中性粒细胞未增加。停用羟基脲6周后，臭氧暴露后反应性和上皮中性粒细胞显著增加。结果表明，臭氧诱导的高反应性可能取决于中性粒细胞向气道的动员。
