Fine structure of early cartilage calcification

摘要: Cartilage at an early stage of calcification, as shown by electron microscope study costochondral junctions 1-month-old guinea pigs, and proximal tibial—distal femoral epiphyses 3-day-old rats, is characterized the formation osmiophilic, PAS-reactive, roundish bodies, having amorphous structure pericellular distribution. Calcification starts inside these which gradually become filled with crystallites. These form clusters, coalesce, surrounding collagenous fibrils, cartilage matrix becomes entirely calcified. Decalcification means EDTA, hydrochloric acid, or formic acid removes all crystallites from sections. However, if decalcification performed PTA, uranyl acetate and/or lead citrate staining follows organic framework revealed in place each apatite crystallite. This partially extracted carried out before embedding. It suggested that may nucleate calcium salts it intrinsic component