The extracellular matrix (ECM) comprises a large proportion of the lung parenchymal tissue and is an important contributor to the mechanical properties of the lung. The lung tissue is a biologically active scaffold with a complex ECM matrix structure and composition that provides physical support to the surrounding cells. Nearly all respiratory pathologies result in changes in the structure and composition of the ECM; however, the impact of these alterations on the mechanical properties of the tissue is not well understood. In this study, a novel network model was developed to incorporate the combinatorial effect of lung tissue ECM constituents such as collagen, elastin and proteoglycans (PGs) and used to mimic the experimentally derived length–tension response of the tissue to uniaxial loading. By modelling the effect of collagen elasticity as an exponential function with strain, and in concert with the linear elastic response of elastin, the network model’s mechanical response matched experimental stress–strain curves from the literature. In addition, by incorporating spring–dashpot viscoelastic elements, to represent the PGs, the hysteresis response was also simulated. Finally, by selectively reducing volume fractions of the different ECM constituents, we were able to gain insight into their relative mechanical contribution to the larger scale tissue mechanical response.

细胞外基质 (ECM) 占肺实质组织的很大一部分，是肺机械性能的重要贡献者。肺组织是一种生物活性支架，具有复杂的 ECM 基质结构和成分，可为周围细胞提供物理支持。几乎所有的呼吸系统疾病都会导致 ECM 的结构和组成发生变化；然而，这些改变对组织机械性能的影响尚不清楚。在这项研究中，开发了一种新的网络模型，以结合肺组织 ECM 成分（如胶原蛋白、弹性蛋白和蛋白聚糖 (PG)）的组合效应，并用于模拟实验得出的组织对单轴载荷的长度-张力响应。通过将胶原弹性的影响建模为应变的指数函数，并与弹性蛋白的线性弹性响应一致，网络模型的机械响应与文献中的实验应力-应变曲线相匹配。此外，通过结合弹簧缓冲器粘弹性元件来表示 PG，还模拟了滞后响应。最后，通过有选择地减少不同 ECM 成分的体积分数，我们能够深入了解它们对更大规模组织机械响应的相对机械贡献。为了代表 PG，还模拟了滞后响应。最后，通过有选择地减少不同 ECM 成分的体积分数，我们能够深入了解它们对更大规模组织机械响应的相对机械贡献。为了代表 PG，还模拟了滞后响应。最后，通过有选择地减少不同 ECM 成分的体积分数，我们能够深入了解它们对更大规模组织机械响应的相对机械贡献。