Lung Tissue Compliance Interacts with Smooth Muscle and Drives Hyperresponsiveness in Mice with Experimental Asthma.

Introduction: A recent study on BALB/c and C57BL/6 mice demonstrated a clear lack of association between the in vivo response to nebulized methacholine and the degree of airway narrowing ex vivo in a model of asthma induced by a daily exposure to house dust mite over 10 consecutive days. This finding raises the question of which factors determine the methacholine response in vivo.

Methods: Herein, multiple linear regression analyses were used to determine which baseline physiological characteristics are associated with the methacholine response.

Results: Among the 10 baseline characteristics studied, and depending on how the methacholine response was monitored during a concentration-response, lung tissue compliance was the most commonly and robustly associated with the methacholine response. Inspiratory capacity was the second most frequently associated.

Conclusion: These results suggest that lung tissue compliance and inspiratory capacity may be two important determinants of the methacholine response in BALB/c and C57BL/6 mice with and without experimental asthma.