Localization and turnover of calcium in biominerals (otoconia, bone and teeth).

研究了焦锑酸析出钙在钙化体系中的定位。样品用焦锑酸法固定，用氯化铵处理选择性脱钙。结果表明：1.用焦锑和戊二醛固定(两步法)比直接浸泡在焦锑和四氧化二臭氧中(一步法)能更好地保存组织和定位沉淀物。在树蛙的内淋巴囊中，沉淀物分布在碳酸钙晶体周围。当晶体生长加速时，析出物的数量增加。这些晶体被认为是通过吸积生长的。在大鼠和豚鼠内耳的耳石器官中，在耳锥周围可见沉淀物，存在亚甲胺银阳性物质。在幼年大鼠的骨中，沉淀常见于成骨细胞的内质网、破骨细胞的空泡和褶皱边缘。焦锑酸钙在脱钙骨中的分布与未脱钙骨中的分布一致。经氯化铵处理后，焦锑酸钙的沉淀物被很好地保留下来，组织的精细结构也得到了很好的保存。用X射线微区分析和EGTA萃取证实了沉淀物中钙的存在。

The localization of pyroantimonate-precipitable calcium was examined in calcifying systems. Specimens were fixed by the pyroantimonate method and selectively decalcified by treatment with ammonium chloride. After this treatment, otolithic organs and young bones were easy to cut into sections and following results were obtained:1.The fixation with pyroantimonate and glutaraldehyde (two step method) resulted in better preservation of tissue and more precise localization of precipitaes than did the direct immersion of specimens in pyroantimonate and osmium tetroxide (one step method).2. In the endolymphatic sac of the tree frog, the precipitate was distributed around calcium carbonate crystals. When crystalline growth was accelerated, the precipitate increased in amount. These crystals were considered to grow by accretion.3. In the otolithic organs in the inner ear of the rat and guinea pig, the precipitate was found around otoconia where a silver methenamine-positive material existed.4. In bone of very young rats, the precipitate was frequently observed within the endoplasmic reticulum of obsteoblasts, and on vacuoles and the ruffled border of osteoclasts. The distribution of calcium pyroantimonate in decalcified bone was the same as that in undecalcified counterparts.5. The precipitates of calcium pyroantimonate were well retained and the fine structure of the tissue was well preserved after the treatment with ammonium chloride.6. The presence of calcium in the precipitates was confirmed by X-ray microanalysis and extraction with EGTA.