在单轴和双轴拉伸测试中,尿液膀光滑肌肉组织的活性和被动物质反应
Julian Geldner1, Stefan Papenkort1, Simon Kiem1
1Department of Sport and Motion Science, University of Stuttgart, Stuttgart, Germany.
Acta biomaterialia
|December 20, 2024
概括
这项研究揭示了不同的拉伸方法如何影响猪膀平滑肌肉机制. 双轴拉伸减缓激活并改变最佳拉伸,为器官建模和生物材料开发提供了关键的见解.
科学领域:
- 生物力学 生物力学
- 生物材料科学 生物材料科学
- 生理学 生理学 生理学
背景情况:
- 膀的机械特性对其功能至关重要.
- 了解光滑肌肉机制是理解空洞器官生理学的关键.
- 现有的研究主要使用单轴拉伸,限制了对多轴变形效应的洞察力.
研究的目的:
- 为了研究单轴和双轴拉伸对猪尿膀平滑肌肉力学的影响.
- 在不同的变形模式下分析应力放松,激活动态和活性应力拉伸关系.
- 开发和验证一个连续机械模型来解释实验发现.
主要方法:
- 在36个猪尿膀组织样本上进行了单轴和双轴拉伸试验.
- 分析了压力放松,激活动态 (τact) 和被动/主动压力伸展反应 (λopt, σopt).
- 开发了一种具有活跃肌肉纤维的粘弹性,同otropic 固体模型来解释结果.
主要成果:
- 应力放松时间常数取决于拉伸幅度,无论是单轴测试还是双轴测试.
- 与单轴拉伸相比,双轴拉伸导致了较慢的激活 (τact增加了63%) 和降低了最佳拉伸 (λopt减少了18%) .
- 最大活性应力 (σopt) 在单轴和双轴测试之间没有显著差异.
- 模型预测与实验结果保持一致,通过纤维方向和活性应力伸展关系来解释差异.
结论:
- 变形模式显著影响平滑肌肉机制,影响激活动态和最佳拉伸.
- 均轴拉伸为膀光滑肌的行为提供了独特的洞察力,这些洞察力仅仅通过单轴测试无法捕获.
- 这些发现增强了对膀生理学的理解,提高了器官建模的准确性,并为肌肉应用的生物材料设计提供了信息.
相关概念视频
01:13Cell-matrix's Response to Mechanical Forces
2.7K
In animal cells, the extracellular matrix allows cells within tissues to withstand external stresses and transmits signals from the outside of the cell to the inside. The extracellular matrix is extensive, and its composition varies between different types of tissues. For example, the reticular fibers and ground substance make up the ECM in loose connective tissue, while collagen and bone minerals make up the ECM of bone tissue.
Anchoring junctions mechanically attach a cell to the...
Anchoring junctions mechanically attach a cell to the...
2.7K
01:20Normal Strain under Axial Loading
1.6K
Normal strain under axial loading is an important concept in the field of mechanics of materials. Axial loading implies the application of a force along the axis of a material, like a column or bar. This force can either compress or stretch the material. In the context of axial loading, normal strain is the deformation experienced by the material in the direction of the loading force. It's calculated as the change in length divided by the original length of the material. This unitless ratio...
1.6K
01:15Relation between Poisson's ratio, Modulus of Elasticity and Modulus of Rigidity
824
Deformation occurs in axial and transverse directions when an axial load is applied to a slender bar. This deformation impacts the cubic element within the bar, transforming it into either a rectangular parallelepiped or a rhombus, contingent on its orientation. This transformation process induces shearing strain. Axial loading elicits both shearing and normal strains. Applying an axial load instigates equal normal and shearing stresses on elements oriented at a 45° angle to the load axis.
824
01:21Deformations in a Transverse Cross Section
716
When a material is subjected to uniaxial stress, it elongates or contracts in the direction of the applied force, and also undergoes changes in the perpendicular directions. This behavior is crucial for understanding how materials behave under stress and is governed by mechanical properties such as Poisson's ratio v, which measures the ratio of transverse strain to axial strain.
As the material stretches, it expands or contracts in orthogonal directions to the load. This phenomenon varies...
As the material stretches, it expands or contracts in orthogonal directions to the load. This phenomenon varies...
716
01:23Behavior of Concrete Under Compressive Load
949
Concrete exhibits specific behaviors under different compressive loads. Understanding this is crucial for understanding its structural integrity. When concrete undergoes uniaxial compression, it tends to develop cracks that run parallel to the direction of the force. These parallel cracks stem from localized tensile stresses that occur perpendicular to the compression direction. Additionally, angled cracks may appear due to the formation of shear planes.
As the concrete specimen fractures under...
As the concrete specimen fractures under...
949