Small and large airway functional changes. A, Acetylcholine mediated contraction of the bronchioles. B, Serotonin mediated contraction of the bronchioles. C, Isoprenaline mediated relaxation acetylcholine pre-contracted bronchioles. D, Carbachol mediated contraction of the trachea of control. E, Isoprenaline mediated relaxation on carbachol pre-contracted trachea of control. Data expressed as Mean ± SEM; n = 16 for all groups. *P < 0.05 PA vs HFHC, †P < 0.05 CON vs HFHC + PA, ‡P < 0.05 HFHC vs HFHC + PA, §P < 0.05 PA vs HFHC + PA.