Torzilli P A
J Orthop Res. 1985;3(4):473-83. doi: 10.1002/jor.1100030410.
The spatial and bulk water equilibrium partition and fluid content were determined for normal adult bovine articular cartilage as a function of pH, temperature, and geometric confinement. Water partition averaged 60 +/- 7% at neutral pH and 37 degrees C and increased with decreasing pH and increasing temperature without a concomitant change in fluid content. The variation in water partition appeared to be a result of local conformation changes in the collagen fibril ultrastructure causing a transfer between free and trapped water volume. Removal of the lateral and subchondral bone geometric constraints caused an increase in both the water partition and fluid content. However, this partition variation could be accounted for solely from a change in free fluid volume without a change in the trapped fluid volume. These results suggest that in articular cartilage the proteoglycan-collagen interaction may be an important mechanism for controlling the partition of water between a freely exchangeable space and a space allowing no fluid exchange.
测定了正常成年牛关节软骨的空间和总体水平衡分配及流体含量，作为pH值、温度和几何约束的函数。在中性pH值和37摄氏度时，水平均分配为60±7%，并随着pH值降低和温度升高而增加，而流体含量没有相应变化。水平分配的变化似乎是胶原纤维超微结构局部构象变化的结果，导致自由水体积和滞留水体积之间的转移。去除外侧和软骨下骨的几何约束会导致水平分配和流体含量增加。然而，这种分配变化可能仅由自由流体体积的变化引起，而滞留流体体积没有变化。这些结果表明，在关节软骨中，蛋白聚糖-胶原相互作用可能是控制水在自由交换空间和不允许流体交换空间之间分配的重要机制。
