CAMERON D A, ROBINSON R A
J Biophys Biochem Cytol. 1956 Jul 25;2(4 Suppl):253-60. doi: 10.1083/jcb.2.4.253.
An examination of the fine structure of cartilage and bone matrix at the distal epiphyseal line of the femur of a newborn infant has revealed the following information. Cartilage matrix is composed of a network of widely spaced fibers without obvious periodic banding. Calcification is first seen about the level of the third chondrocyte capsule distal to the furthest penetration of the capillaries. It starts as a haphazard deposition of crystals which have no obvious relationship to the location of the fibers. The process of calcification is completed before ossification commences but the central zone of matrix remains only partly mineralized. Bone matrix is formed over a bar of calcified cartilage. Fibers, recognizable as collagen, are deposited in a loose network in a narrow zone between the osteoblasts and cartilage. These fibers are 2 to 5 times as wide as the fibers in epiphyseal cartilage. Calcification then begins in the osteoid, crystals being first laid down irregularly on or close to the fibers. As they increase in number, the crystals tend to line up along the fibers and eventually are arranged so that the periodicity of the underlying collagen is emphasized. In such an area the fibers are more tightly packed than when uncalcified. There is no change observed in the calcified cartilage at this level. The extracellular matrices of this epiphyseal cartilage and bone can be distinguished from one another in the electron microscope.
对一名新生儿股骨远端骨骺线处软骨和骨基质的精细结构进行检查后，得出了以下信息。软骨基质由间距很宽的纤维网络组成，没有明显的周期性条纹。钙化首先出现在毛细血管最远穿透点远端第三个软骨细胞囊的水平附近。它开始于晶体的随机沉积，这些晶体与纤维的位置没有明显关系。钙化过程在骨化开始之前完成，但基质的中心区域仍只有部分矿化。骨基质在一条钙化软骨条上形成。可识别为胶原蛋白的纤维沉积在成骨细胞和软骨之间的狭窄区域内的疏松网络中。这些纤维的宽度是骨骺软骨中纤维的2至5倍。然后类骨质开始钙化，晶体首先不规则地沉积在纤维上或纤维附近。随着晶体数量的增加，它们倾向于沿着纤维排列，最终排列方式使得下面胶原蛋白的周期性得到强调。在这样的区域中，纤维比未钙化时排列得更紧密。在这个水平上，钙化软骨没有观察到变化。在电子显微镜下，可以区分这种骨骺软骨和骨的细胞外基质。
