Fig. 1.

Changes in airway resistance (Rl) and compliance (Cl) in a caveolin-1 knockout (Cav1 KO) mouse model of allergic airway hyperresponsiveness induced by ovalbumin (OVA) sensitization and challenge. Wild-type (WT) and Cav1 KO animals either were unsensitized (control; CTL) or were OVA sensitized/challenged. Rl and Cl were measured under anesthesia, paralysis, and mechanical ventilation via tracheostomy (see methods for details) to increasing doses of methacholine (0–50 mg/ml). Baseline Rl was higher in both CTL and OVA Cav1 KO mice compared with WT and increased substantially with methacholine (A). In the Cav1 KO groups these values were significantly greater than in any of the other 3 groups. Cl values were significantly smaller in Cav1 KO mice (B). In the OVA Cav1 KO group, Cl dropped rapidly and significantly with increasing methacholine. Values are means ± SE (n = 5 per group). *Significant difference between WT and Cav1 KO; #significant difference between CTL and OVA (P < 0.05).