Fig. 2.

House dust mite and ozone co-exposure induce airway hyperresponsiveness. A) Methacholine dose response of Newtonian resistance (Rn) and provocative concentration 100 (PC₁₀₀) calculation for HDM and HDM + O₃ groups (inset) B) Methacholine dose response of tissue damping (G) C) Methacholine dose response of tissue elastance (E). D). tissue Hysteresivity (η) calculated as G/H E) % change in Forced Expiratory Flow at 0.1s (FEV_0.1) after exposure to increasing methacholine doses and inset is provocative concentration 30 (PC₃₀) calculation for FEV0.1. F) Impedance plots at 50 μg/mL methacholine with specific small airway resistance and reactance plotted as bar graphs. Respiratory impedance was measured using the forced oscillation technique with pseudo-random oscillations over a range of 1–20.5 Hz depicting the real (i.e., resistance) and imaginary (i.e., reactance) part of the impedance. Mice were exposed to PBS + Air, PBS + ozone (1 ppm; 3 h), HDM + air, HDM + ozone (1 ppm; 3 h). Data are presented as mean ± SD of n = 5–9 mice per group and analyzed by two-way analysis of variance (ANOVA) followed by Tukey's post hoc test or students t-test. *P ≤ 0.05 vs PBS + Air, ε P ≤ 0.05 between HDM + Air and HDM + O₃ that methacholine concentration. For Impedance measurements *P ≤ 0.05, **P ≤ 0.01, ***P ≤ 0.001, ****P ≤ 0.0001.