The Intracellular Localization of Inorganic Cations With Potassium Pyroantimonate

Abstract

Potassium pyroantimonate, when used as fixative (saturated or half-saturated, without addition of any conventional fixative) has been demonstrated to produce intracellular precipitates of the insoluble salts of calcium, magnesium, and sodium and to preserve the general cell morphology. In both animal and plant tissues, the electron-opaque antimonate precipitates were found deposited in the nucleus—as well as within the nucleolus—and in the cytoplasm, largely at the site of the ribonucleoprotein particles; the condensed chromatin appeared relatively free of precipitates. The inorganic cations are probably in a loosely bound state since they are not retained by conventional fixatives. The implications of this inorganic cation distribution in the intact cell are discussed in connection with their anionic counterparts, i.e., complexing of cations by fixed anionic charges and the coexistence of a large pool of inorganic orthophosphate anions in the nucleus and nucleolus.

Structure and organization of odontoblasts

“…To elucidate further the potential role of the odontoblast in dentin mineralization, calcium distribution at the subcellular level of odontoblasts has been examined by various methods including electron microscopic autoradiograph of 45Ca (Nagai and Frank, 1974), light microscopic &a autoradiography on freeze-dried sections (Kawamoto and Shimizu, 19941, potassium-pyroantimonate cytochemistry (Lane and Martin, 1969;Legato and Langer, 1969;Tandler et al, 1970;Reith, 1976;Lyaruu et al, 19871, analysis of frozen ultrathin sections (Landis and Glimcher, 1978;Ozawa and Yamamoto, 19831, and inert dehydration tissue processing (Landis et al, 1977). In addition, an anhydrous fixation technique for electron microscopy using nonaqueous fixatives was applied to osteoblasts (Manston and Katchburian, 1983) and ameloblasts (Sasaki et al, 1987).…”

Use of electron spectroscopic imaging to determine element composition of the melanin granules in the stria vascularis of the guinea pig

“…This kind of calcium, which forms electron-dense reaction products after the application of potassium antimonate, belongs to the loosely bound exchangeable calcium pool [4,21,25]. The calcium detected in the melanin granules must be bound so tightly to some proteins or structural components within these cell structures that it is unable to react with the applied potassium antimonate.…”

Localisation of intracellular calcium in the neutrophil through the selective precipitation with the antimonate ion

“…2,3 Die selektiwiteit vir kalsiumione in die teenwoordigheid van ander katione word grootliks bepaal deur die tipe buffers, die pH van die buffers, die antimonaatioonkonsentrasies, die tipe fikseermiddels en die weefselvoorbereiding, wat almal die retensie en presipitering van die fisiologiese katione relatief tot mekaar bepaal. 2,4 Die metode vir die lokalisering van intrasellulêre kalsium berus op a) die stabilisering en/of die binding van kalsium deur óf fosfaat óf oksalaatanione gedurende primêre fiksering met glutaaraldehied (fosfaat en oksalaat kan teoreties kalsium in verskillende kalsiumkompartemente bind), b) die daaropvolgende uitwas van alle niegebinde katione en c) die vorming van 'n elektrondigte en nie-oplosbare kalsiumantimonaatsout van die gekomplekseerde of gebonde kalsium gedurende postfiksering. 2,5 Om die subsellulêre verspreiding van kalsium in die neutrofiel te kan ondersoek, moet daar eerstens geskikte transmissie-elektronmikroskopiepreparate voorberei word.…”