The Three-Dimensional Spatial Relationship Between the Collagen Fibrils and the Inorganic Calcium-Phosphate Crystals of Pickerel and Herring Fish Bone

Abstract

High-voltage (1.0 mega-volt) electron stereomicroscopy has been used to examine the spatial relationship between the inorganic crystals and the collagen fibrils of pickerel and herring bone. Stereomicrographs of cross sections of the collagen fibrils encompassing regions of initial to full mineralization showed that the calcium phosphate crystals are located within the collagen fibrils. In all stages of mineralization, calcium-phosphate deposits were not observed associated or within membrane-bound structures. Serial cross sections of the fully mineralized collagen fibrils were three-dimensionally reconstructed using the computer graphic imaging process. Findings from this study suggest that there exist a local "bulging" along the fibrils corresponding to the 680 A periodicity in which additional mass of minerals were observed to be accommodated within the collagen fibril structure at this sites.