Abraham W M, Januszkiewicz A J, Mingle M, Welker M, Wanner A, Sackner M A
J Appl Physiol Respir Environ Exerc Physiol. 1980 May;48(5):789-93. doi: 10.1152/jappl.1980.48.5.789.
This study was undertaken to determine whether measurements of tracheal mucous velocity or airway reactivity to inhaled carbachol more sensitively detect airway effects of inhaled ozone (O3) in conscious sheep. Dose-response curves of mean pulmonary flow resistance (RL) to carbachol were obtained by measuring RL after five breaths of carbachol aerosol with stepwise increases in drug concentration. The animals then breathed 0.5 ppm O3 through an endotracheal tube for 2 h. The dose-response curves were repeated immediately after the 0.5 ppm O3 exposure and 24 h later. In the eight sheep studied, there were no significant alterations in base-line RL immediately after or 24 h after 0.5 ppm O3. Airway hyperreactivity was not apparent immediately after the sheep breathed 0.5 ppm O3, but it was evident 24 h later. In contrast, six sheep that breathed 0.5 ppm O3 in the same manner for 2 h did not show a significant depression in tracheal mucous velocity the same day or 24 h later. Exposure to 1 ppm O3 for 2 h resulted in airway hyperreactivity immediately after the exposure and elevated base-line RL 24 h later; 2 ppm O3 produced an increase in base-line RL immediately after exposure. We conclude that, in conscious sheep, airway hyperreactivity appears to be a more sensitive indicator of airway effects produced by short-term exposure to 0.5 ppm O3 than depression of tracheal mucous velocity.
本研究旨在确定气管黏液速度测量或对吸入卡巴胆碱的气道反应性是否能更灵敏地检测清醒绵羊吸入臭氧（O3）后的气道效应。通过在卡巴胆碱气雾剂五次呼吸后，随着药物浓度逐步增加测量平均肺血流阻力（RL），获得RL对卡巴胆碱的剂量反应曲线。然后，动物通过气管内导管吸入0.5 ppm O3，持续2小时。在0.5 ppm O3暴露后立即和24小时后重复剂量反应曲线。在研究的八只绵羊中，0.5 ppm O3暴露后立即或24小时后，基线RL无显著变化。绵羊吸入0.5 ppm O3后气道高反应性并不明显，但在24小时后明显。相比之下，以相同方式吸入0.5 ppm O3 2小时的六只绵羊在当天或24小时后气管黏液速度均未出现显著降低。暴露于1 ppm O3 2小时导致暴露后立即出现气道高反应性，24小时后基线RL升高；暴露于2 ppm O3后立即导致基线RL升高。我们得出结论，在清醒绵羊中，气道高反应性似乎是短期暴露于0.5 ppm O3产生的气道效应比气管黏液速度降低更敏感的指标。
