EFFECTS OF PROTEOGLYCAN EXTRACTION ON THE TENSILE BEHAVIOR OF ARTICULAR-CARTILAGE
EFFECTS OF PROTEOGLYCAN EXTRACTION ON THE TENSILE BEHAVIOR OF ARTICULAR-CARTILAGE
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DOI：
10.1002/jor.1100080307
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发表时间：
1990-05-01
影响因子：
2.8
通讯作者：
EYRE, DR
中科院分区：
文献类型：
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作者：
SCHMIDT, MB;MOW, VC;EYRE, DR
我们进行了跨学科的生物力学和生物化学研究，以探索蛋白聚糖总量影响牛关节软骨在张力下的动态和静态行为的程度和方式。使用了两种生物力学测试：(a) 粘弹性蠕变测试和 (b) 缓慢恒速单轴拉伸测试；使用两种酶促蛋白聚糖提取程序：（a）软骨素酶（ABC 处理和（b）用软骨素酶 ABC、胰蛋白酶和链霉菌透明质酸酶连续酶处理。我们发现所有软骨标本的粘弹性蠕变响应可分为两个不同的阶段：初始阶段（< 15 s），其特征是施加负载后应变快速增加，以及后期阶段（15 秒≤t < 25,000 秒），其特征是应变逐渐增加。这项研究的一个主要发现是，蠕变响应的动力学很大程度上受到组织中糖胺聚糖含量的影响。对于未处理的样本和对照样本，初始响应占总应变的约 50%，而对于软骨素酶 ABC 和连续提取的样本，初始响应占总应变的 83%。此外，大多数未经处理的样品和对照样品在 25,000 秒的测试时间内没有达到平衡，而酶消化的样品通常在不到 100 秒的时间内达到平衡。因此，我们得出结论，通过它们对胶原的物理约束，组织中存在的大量蛋白聚糖可在拉伸载荷下阻止纤维重组和排列，从而有效地防止胶原网络的突然延伸。张力实验表明，基本上完全提取蛋白聚糖糖胺聚糖不会显着影响软骨样本或胶原蛋白网络的内在拉伸刚度和强度，因此，软骨中的大量蛋白聚糖（即大聚集型）的一个重要功能是在突然施加拉伸载荷时延缓拉伸和排列的速率，这种机制可能有助于在生理情况下保护软骨胶原蛋白网络。一个关节。
We undertook an interdisciplinary biomechanical and biochemical study to explore the extent and manner in which the total pool of proteoglycans influences the kinetic and static behavior of bovine articular cartilage in tension. Two biomechanical tests were used: (a) the viscoelastic creep test and (b) a slow constant-rate uniaxial tension test; and two enzymatic proteoglycan extraction procedures were used: (a) chondroitinase (ABC treatment and (b) a sequential enzymatic treatment with chondroitinase ABC, trypsin, and Streptomyces hyaluronidase. We found that the viscoelastic creep response of all cartilage specimens may be divided into two distinct phases: an initial phase (< 15 s), characterized by a rapid increase in strain following load application, and a late phase (15 s .ltoreq. t < 25,000 s), characterized by a more gradual increase in strain. A major finding of this study is that the kinetics of the creep response is greatly influenced by the glycosaminoglycan content of the tissue. For untreated and control specimens, the initial response comprises about 50% of the total strain, while for chondroitinase ABC and sequentially extracted specimens, the initial response comprises up to 83% of the total strain. Furthermore, most untreated and control specimens did not reach equilibrium within the 25,000 s test period, while enzymatically digested specimens often reached equilibrium in less than 100 s. Thus, we conclude that through their physical restraints on collagen, the bulk of proteoglycan present in the tissue acts to retard fibrillar reorganization and alignment under tensile loading, thereby effectively preventing sudden extension of the collagen network. In contrast, the results of our slow constant-rate uniaxial tension experiment show that essentially complete extraction of proteoglycan glycosaminoglycans does not affect the intrinsic tensile stiffness and strength of cartilage specimens or the collagen network in a significant manner. Hence, an important function of the bulk proteoglycans (i.e., the large aggregating type) in cartilage is to retard the rate of stretch and alignment when a tensile load is suddenly applied. This mechanism may be useful in protecting the cartilage collagen network during physiological situations, where sudden impact forces are imposed on a joint.