Fig. 1

Plethysmography data: Mice were monitored during exposure period and PenH, peak inspiratory volume, peak expiratory volume, volume per minute, and breath frequency. Each result represents the average value over the 6 h exposure. Statistical significance denoted by “a” (treatment vs respective saline control), “b” (1000 ppm CO₂ vs room air treatment), “c” (5000 ppm CO₂ vs room air treatment) and “d” (5000 ppm CO₂ vs 1000 ppm CO₂ treatment). N = 5 mice/group. Minimum, maximum, mean (+ symbol) and median (line) are denoted for each treatment