Abraham W, Chapman G A, Marchette B
Environ Res. 1984 Dec;35(2):430-8. doi: 10.1016/0013-9351(84)90150-6.
The response of specific lung resistance (SRL) to inhalation of 5 and 10 mg/ml carbachol was compared with the response of SRL to intravenous infusion of 2 and 5 micrograms/kg carbachol before and after a 2-day exposure to 0.5 ppm ozone (O3) in eight conscious sheep. Airway reactivity was defined as the slope of the dose-response curve and airway sensitivity as the largest increase in SRL after carbachol challenge. O3 exposure did not alter mean airway reactivity or mean airway sensitivity as determined by inhalation challenge. In contrast, O3 exposure significantly increased mean airway reactivity by 34% (P less than 0.01) and mean airway sensitivity by 31% (P less than 0.01) as assessed by intravenous challenge. The failure of O3 exposure to enhance responsiveness to inhaled carbachol may have been related to decreased airway penetration of the aerosol, possibly due to mucus hypersecretion. However, O3 exposure may have had a direct effect on the airway smooth muscle, thereby explaining the increased response to infused carbachol.
在8只清醒绵羊中，比较了特定肺阻力（SRL）对吸入5和10mg/ml卡巴胆碱的反应与SRL对静脉输注2和5μg/kg卡巴胆碱的反应，这是在暴露于0.5ppm臭氧（O3）2天之前和之后进行的。气道反应性定义为剂量反应曲线的斜率，气道敏感性定义为卡巴胆碱激发后SRL的最大增加量。通过吸入激发测定，O3暴露并未改变平均气道反应性或平均气道敏感性。相比之下，通过静脉激发评估，O3暴露使平均气道反应性显著增加了34%（P<0.01），平均气道敏感性显著增加了31%（P<0.01）。O3暴露未能增强对吸入卡巴胆碱的反应性，可能与气溶胶的气道穿透性降低有关，这可能是由于黏液分泌过多所致。然而，O3暴露可能对气道平滑肌有直接作用，从而解释了对输注卡巴胆碱反应的增加。
