Electrostatic and non-electrostatic contributions of proteoglycans to the compressive equilibrium modulus of bovine articular cartilage.
Electrostatic and non-electrostatic contributions of proteoglycans to the compressive equilibrium modulus of bovine articular cartilage.
复制标题
DOI：
10.1016/j.jbiomech.2010.01.021
复制
发表时间：
2010-05-07
影响因子：
2.4
通讯作者：
Ateshian, Gerard A.
中科院分区：
文献类型：
--
作者：
Guterl, Clare Canal;Hung, Clark T.;Ateshian, Gerard A.
这项研究提供了直接的实验证据，评估蛋白多糖的静电和非静电的贡献，牛关节软骨的压缩平衡模量。未成熟和成熟的牛软骨样品进行了测试，在无侧限压缩和它们的深度依赖性的平衡压缩模量测定使用应变测量与数字图像相关分析。通过在等渗和高渗盐水中测试样品来评估静电贡献;通过测试未处理和去除蛋白聚糖的样品来评估组合贡献。虽然它是公认的蛋白聚糖有助于显着的压缩刚度的软骨，结果表明，组合的静电和非静电的贡献可以加起来超过98%的模量，以前没有意识到的幅度。在这一贡献中，约三分之二来自静电效应。蛋白聚糖耗尽的软骨基质的压缩模量可以低至3 kPa，代表小于正常组织模量的2%;实验证据还证实，消化的软骨中的胶原蛋白基质可以在压缩应变下弯曲，导致卷曲模式。因此，将胶原蛋白建模为只能维持张力的纤维基质是合理的。这项研究还表明，软骨中的残余应力并不完全来自蛋白聚糖，因为软骨保持卷曲相对于其原位几何形状，即使在蛋白聚糖耗尽。这些增加的洞察软骨的结构-功能关系，可以导致改进的本构模型和更好地了解软骨的生理负荷条件下的反应。
This study presents direct experimental evidence for assessing the electrostatic and nonelectrostatic contributions of proteoglycans to the compressive equilibrium modulus of bovine articular cartilage. Immature and mature bovine cartilage samples were tested in unconfined compression and their depth-dependent equilibrium compressive modulus was determined using strain measurements with digital image correlation analysis. The electrostatic contribution was assessed by testing samples in isotonic and hypertonic saline; the combined contribution was assessed by testing untreated and proteoglycan-depleted samples. Though it is well recognized that proteoglycans contribute significantly to the compressive stiffness of cartilage, results demonstrate that the combined electrostatic and non-electrostatic contributions may add up to more than 98% of the modulus, a magnitude not previously appreciated. Of this contribution, about two-thirds arises from electrostatic effects. The compressive modulus of the proteoglycan-depleted cartilage matrix may be as low as 3 kPa, representing less than 2% of the normal tissue modulus; experimental evidence also confirms that the collagen matrix in digested cartilage may buckle under compressive strains, resulting in crimping patterns. Thus, it is reasonable to model the collagen as a fibrillar matrix that can only sustain tension. This study also demonstrates that residual stresses in cartilage do not arise exclusively from proteoglycans, since cartilage remains curled relative to its in situ geometry even after proteoglycan depletion. These increased insights into the structure-function relationships of cartilage can lead to improved constitutive models and a better understanding of the response of cartilage to physiological loading conditions.
登录
查看更多内容
DOI：
10.3109/17453679509157645
发表时间：
1995-10-01
期刊：
ACTA ORTHOPAEDICA SCANDINAVICA
影响因子：
--
作者：
Bonassar, LJ;Jeffries, KA;Grodzinsky, AJ
通讯作者：
Grodzinsky, AJ
影响因子：
3.8
作者：
Kovach, IS
通讯作者：
Kovach, IS
影响因子：
--
作者：
LOTKE, PA;GRANDA, JL
通讯作者：
GRANDA, JL
影响因子：
2.4
作者：
Ateshian, GA;Chahine, NO;Hung, CT
通讯作者：
Hung, CT
影响因子：
2.4
作者：
Dean, Delphine;Han, Lin;Ortiz, Christine
通讯作者：
Ortiz, Christine