Nakamura K, Ohta N, Kawaji W, Takata K, Hirano H
Arch Histol Jpn. 1984 Nov;47(5):541-7. doi: 10.1679/aohc.47.541.
Changes in permeability of adult rabbit articular cartilage caused by joint contracture were studied by light and transmission electron microscopy, employing horseradish peroxidase (HRP) as an indicator. The knee joint was plaster-immobilized for 0, 2, 4, 6, or 8 weeks in the flexion position. One ml of 4% HRP was administered in the articular cavity of the knee joint and allowed to diffuse and permeate into the articular cartilage. Distribution of the permeated HRP was visualized in the cartilage taken from the lateral condyle of the femur, utilizing the DAB-H2O2 reaction. In the normal and the non-immobilized joints, the permeated HRP reached to the matrix and chondrocytes situated in the deep layer of the articular cartilage. HRP was heavily deposited in the intercellular matrices, particularly around the chondrocytes, and was actively endocytosed by these cells. In the plaster-immobilized joints, especially after 4 weeks or longer of immobilization, the administered HRP had not permeated well and was restricted to the surface (lamina splendens) and the superficial layer of the cartilage. These results show that administered HRP diffuses into the deep layer of the articular cartilage and is actively endocytosed by chondrocytes and that the permeability of articular cartilage is remarkably reduced by joint contracture.
以辣根过氧化物酶（HRP）为指示剂，通过光学显微镜和透射电子显微镜研究关节挛缩对成年兔关节软骨通透性的影响。将膝关节在屈曲位用石膏固定0、2、4、6或8周。在膝关节腔注射1ml 4%的HRP，使其扩散并渗透到关节软骨中。利用DAB-H2O2反应，观察股骨外侧髁软骨中渗透的HRP的分布情况。在正常和未固定的关节中，渗透的HRP可到达关节软骨深层的基质和软骨细胞。HRP大量沉积在细胞间基质中，尤其是软骨细胞周围，并被这些细胞主动内吞。在石膏固定的关节中，尤其是固定4周或更长时间后，注入的HRP渗透不佳，局限于软骨的表面（亮层）和浅层。这些结果表明，注入的HRP可扩散到关节软骨深层并被软骨细胞主动内吞，且关节挛缩会显著降低关节软骨的通透性。
