Dose response curves to inhaled methacholine. Dose response curves (expressed as a % of the response to saline aerosol) for mice systemically sensitised with OVA/Alum and challenged via the airways with 1 (left), 3 (centre) or 6 (right) OVA aerosols. Mice were challenged 24 (●) or 48 (▲) hours after the last OVA aerosol. Dose response curves from naïve mice (○) are also shown. All data are expressed as mean ± SEM (n = 7–8). * indicates significance (p < 0.05 vs naïve mice; ANOVA on Ranks, Dunn's post-hoc for Raw and G; ANOVA, Tukey's post-hoc for H).