Assessment of MCH-induced AHR 4 h after treatment with LPS (via OPA) in WT and Htr4−/− mice. Whole lung resistance (R), Newtonian resistance (Rn), tissue resistance (G), compliance (C), elastance (E), and tissue elastance (H) were measured with flexiVent. Mean values per group with sem are plotted (n ≥ 7/genotype). *P < 0.05 vs. WT.