Mechanics of pulmonary airways: Linking structure to function through constitutive modeling, biochemistry, and histology

摘要: Breathing involves fluid-solid interactions in the lung; however, lack of experimental data inhibits combining mechanics air flow to airway deformation, challenging understanding how biomaterial constituents contribute tissue response. As such, lung research is increasingly focused on exploring relationship between structure and function. To address these needs, we characterize mechanical properties porcine airways using uniaxial tensile experiments, accounting for bronchial orientation- location- dependency. Structurally-reinforced constitutive models are developed incorporate role collagen elastin fibers embedded within extrafibrillar matrix. The strain-energy function combines a matrix description (evaluating six models: compressible NeoHookean, unconstrained Ogden, uncoupled Mooney-Rivlin, incompressible Demiray NeoHookean), superimposed with non-linear two exponential polynomial). best formulation representative all regions determined based curve-fit results data, uniqueness sensitivity. Glycosaminoglycan composition, alongside architecture, indicate fiber form be primarily responsible observed anisotropy heterogeneous behavior. authors' knowledge, this study first formulate structurally-motivated model, augmented biochemical analysis microstructural observations, investigate proximal distal bronchi. Our systematic pulmonary characterization provides necessary foundation mechanics; furthermore, enable clinical translation through simulations obstruction disease, fluid-structure interaction insights during breathing, potentially, predictive capabilities medical interventions. STATEMENT OF SIGNIFICANCE: advancement relies investigating biomechanical response tree. Experiments demonstrating non-linear, heterogeneous, anisotropic material behavior used develop structural model Calibrated parameters exhibit regional variation properties, initially hypothesized originate from constituents. Further exploration histological indicates governed by form. can directly finite element physiologically relevant more accurate computational aimed help diagnose monitor disease.