Yamada M
Arch Histol Jpn. 1976 Nov;39(5):347-78. doi: 10.1679/aohc1950.39.347.
Ultrastructural and cytochemical studies on developing tendon-bone joints (fibrocartilage) of rats indicated that the initial calcification loci were, as in some other calcifying tissues, matrix vesicles. These membrane-bounded vesicular structures were concentrated in the spaces between the longitudinal cell columns of the fibrocartilage. Where calcification was going to start, the vesicles became denser and more osmiophilic in appearance. The first identifiable needles of apatite crystals were deposited in and close to the matrix vesicles. Where calcification was more extensive and crystals radiating from each calcification center formed a calcified spherule, the matrix vesicles were no longer deposits of minerals was noticed at the site of the initial calcification. Alkaline phosphatase activity was demonstrated in the matrix vesicles as well as in the plasma membrane of fibrocartilage cells, most intensely at the initiating site of calcification. Following potassium pyroantimonate fixation to produce electron opaque deposits of calcium, the deposits were located mainly in the mitochondria and plasma membrane of fibrocartilage cells as well as in matrix vesicles. The closer to the initial site of calcification, the stronger the cells and vesicles reacted. In the area where calcification was in progress, however, calcium was gradually lost from the cell and reversely accumulated in the matrix vesicles. The ultrastructural and cytochemical findings from this study suggested that they were of cellular origin and liberated into the matrix from cells, partly by way of budding off and partly by cell disintegration. The possible roles of matrix vesicles at the initiating sites of calcification in fibrocartilage were discussed.
对大鼠发育中的肌腱-骨连接（纤维软骨）进行的超微结构和细胞化学研究表明，与其他一些钙化组织一样，最初的钙化位点是基质小泡。这些有膜包被的囊泡结构集中在纤维软骨纵向细胞柱之间的间隙中。在即将开始钙化的部位，小泡在外观上变得更致密且嗜锇性更强。最早可识别的磷灰石晶体针状结构沉积在基质小泡内及其附近。在钙化更广泛且从每个钙化中心辐射出的晶体形成钙化球的地方，基质小泡不再存在，在最初钙化部位未发现矿物质沉积。碱性磷酸酶活性在基质小泡以及纤维软骨细胞的质膜中均有显示，在钙化起始部位最为强烈。在用焦锑酸钾固定以产生钙的电子不透明沉积物后，沉积物主要位于纤维软骨细胞的线粒体和质膜以及基质小泡中。离钙化起始部位越近，细胞和小泡的反应越强。然而，在钙化进行的区域，钙逐渐从细胞中流失并反向积累在基质小泡中。这项研究的超微结构和细胞化学结果表明，它们起源于细胞，并部分通过出芽和部分通过细胞解体从细胞释放到基质中。讨论了基质小泡在纤维软骨钙化起始部位的可能作用。
