Krefting E R, Barckhaus R H, Höhling H J, Bond P, Hosemann R
Cell Tissue Res. 1980;205(3):485-92. doi: 10.1007/BF00232288.
Mineralized pieces of tendons from the tibio-tarsus of turkeys were (i) shock-frozen, freeze-dried, embedded and cut without staining, or (ii) fixed, embedded and stained after sectioning. Micrographs were taken with an electron microscope on longitudinally cut sections. The center-to-center distances of neighboring apatitic needles within collagen fibrils were measured. For shock-frozen and freeze-dried specimens, the average of these distances is 4.7 nm and the most frequent value 4.2 nm; for the fixed and stained specimens, 3.8 nm and 3.6 nm, respectively. Laser diffraction of the electron micrographs showed a dumbbell-like intensity pattern (two diffuse maxima of intensity on the equator, one on each side of the central spot), giving an average distance of about 6 nm. This value represents the upper range of the direct measurements. The measurements demonstrate that the arrangement of the collagen microfibrils is mainly preserved during mineralization. However, using laser diffraction, distances of 9-11 nm were also observed. Such large distances can also be demonstrated by X-ray diffraction on collagen fibrils stained under special conditons. this may indicate that special conditions of apatitic mineralization or staining may alter the arrangement of the microfibrils.
(i) 速冻、冻干、包埋并在未染色的情况下切片，或 (ii) 固定、包埋并在切片后染色。使用电子显微镜对纵向切片拍摄显微照片。测量了胶原纤维内相邻磷灰石针的中心距。对于速冻和冻干标本，这些距离的平均值为4.7 nm，最常见的值为4.2 nm；对于固定和染色标本，分别为3.8 nm和3.6 nm。电子显微照片的激光衍射显示出哑铃状强度模式（赤道上有两个强度漫射最大值，在中心点两侧各一个），给出的平均距离约为6 nm。该值代表直接测量的上限。测量结果表明，胶原微纤维的排列在矿化过程中基本得以保留。然而，使用激光衍射时，也观察到了9 - 11 nm的距离。在特殊条件下染色的胶原纤维上进行X射线衍射也能证明存在如此大的距离。这可能表明磷灰石矿化或染色的特殊条件可能会改变微纤维的排列。
