Investigations on trace elements in normal and senile cataractous lenses

Rácz, Péter; Ördögh, M.

doi:10.1007/bf02387418

Cited by 28 publications

(9 citation statements)

References 7 publications

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“…An unexpected finding was the presence of a small peak of rubidium (isotopes at 85 and 87) in normal lens. This has been reported for normal human lenses (Racz & Ordogh, 1977).…”

Section: Analysis Of Normal Lensmentioning

confidence: 55%

Quantitative microlocalization of diffusible ions in normal and galactose cataractous rat lens by secondary ion mass spectrometry

Burns

File

1986

Journal of Microscopy

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Secondary ion mass spectrometry (SIMS) is a surface analytical technique with high sensitivity for elemental detection and microlocalization capabilities within the micrometre range. Quantitative analysis of epoxy resins and gelatin have been reported (Burns-Bellhorn & File, 1979).We report here the first application of this technique to quantitative microlocalization in the context of a physiological problem-analyses of sodium, potassium and calcium in normal and galactose-induced cataract in rat lens. It is known that during the development of galactose-induced cataract the whole lens content of potassium is decreased, sodium is increased and, in late stages, calcium concentration increases. Whether these alterations in diffusible ions occur homogeneously or heterogeneously is not known.Standard curves were generated from epoxy resins containing known concentrations of sodium, potassium or calcium organometallic compounds using the Cameca IMS 300 Secondary Ion Mass Spectrometer. Normal and cataractous lenses were prepared by freezing in isopentane in a liquid nitrogen bath followed by freeze-drying at -30°C. After dry embedding in epoxy resin, 10 pm thick sections of lens were pressure mounted on silicon wafers, overcoated with gold, and ion emission measured under the same instrumental conditions used to obtain the standard curves. Quantitative analysis of an area 27pm in diameter, or a total analysed volume of 1 * 1 pm3, was performed by using a mechanical aperture in the ion optical system. Ion images provided qualitative microanalysis with a lateral resolution of 1 pm.Control rat lenses gave values for sodium and potassium content with a precision of +17% or less. These values were compared to flame photometry and atomic absorption measurements of normal lenses and were accurate within 25%. Analysis of serum and blood also gave accurate and precise measurements of these elements. Normal rat lenses had a gradient of sodium, and, to a lesser degree, of potassium from the cortex to the nucleus.Development of galactose-induced cataract was heterogeneous by morphological criteria, beginning at the lens equator and spreading from the cortex into the nucleus. However, the

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“…An unexpected finding was the presence of a small peak of rubidium (isotopes at 85 and 87) in normal lens. This has been reported for normal human lenses (Racz & Ordogh, 1977).…”

Section: Analysis Of Normal Lensmentioning

confidence: 55%

Quantitative microlocalization of diffusible ions in normal and galactose cataractous rat lens by secondary ion mass spectrometry

Burns

File

1986

Journal of Microscopy

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“…The discrepancy between our results and those of Ahmed might be due to whether or not transition metal ions had been added to the reaction system. In cataracts, lenticular copper ion was found to be condensed, at concentrations 4-10-times higher than normal, in intact lenses (Shlopak, 1962(Shlopak, , 1963(Shlopak, , 1964Nath et al, 1969;Racz & Ordogh, 1977;Cook and McGahan, 1986). These results show that copper-ion-mediated oxidative damage to protein in vivo, especially that concerned with aging and cataracts, may be an important pathway which should be studied further.…”

Section: Discussionmentioning

confidence: 80%

Selective oxidation of histidine residues in proteins or peptides through the copper(II)-catalysed autoxidation of glucosone

Cheng

Uchida

Kawakishi

1992

Biochemical Journal

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Glucosone has been identified as the main intermediate sugar moiety product of the copper(II)-catalysed autoxidation of the Amadori compound [Kawakishi, Tsunehiro & Uchida (1991) Carbohydr. Res. 211, 167-171]. Oxidative fragmentation of the model protein, especially selective degradation of the histidine residue in protein or peptides mediated by the copper(II)-catalysed autoxidation of glucosone, is discussed in this paper. The oxidative damage to protein could be retarded by catalase (EC 1.11.1.16) and EDTA, while superoxide dismutase (EC 1.15.1.1) and hydroxyradical scavengers showed little effect. Through the process of the oxidative degradation of N-benzoylhistidine and other histidine-containing peptides, the oxidation of the imidazole ring in histidine caused by the glucosone-copper(II) system was the same as that by the ascorbate-copper(II) system. These facts suggest that the copper-catalysed autoxidation of glucosone could generate some active-oxygen species causing oxidative damage to protein similar to that caused by the ascorbate-copper(II) system.

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“…Murata and Taura [1975] did not find any difference between opaque and clear lenses. Our earlier [Racz and Ordogh, 1977] and recent mea surements revealed a slightly increased amount of copper in cataractous lenses.…”

Section: Discussionmentioning

confidence: 99%

Cadmium, Lead and Copper Concentrations in Normal and Senile Cataractous Human Lenses

Rácz

Erdöhelyi²

1988

Ophthalmic Res

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Cadmium, lead and copper concentrations were measured in normal and cataractous human lenses by atomic absorption spectrophotometry. The concentrations of all three elements were relatively higher in cataractous lenses compared with normals, and the ratios of cataract/normal concentrations were in the order Pb > Cd > Cu.The concentration of these trace elements also varied according to lense age. It is likely that the major source of cadmium is tobacco smoke while that of lead is the exhaust gases of motor cars.

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Investigations on trace elements in normal and senile cataractous lenses

Cited by 28 publications

References 7 publications

Quantitative microlocalization of diffusible ions in normal and galactose cataractous rat lens by secondary ion mass spectrometry

Quantitative microlocalization of diffusible ions in normal and galactose cataractous rat lens by secondary ion mass spectrometry

Selective oxidation of histidine residues in proteins or peptides through the copper(II)-catalysed autoxidation of glucosone

Cadmium, Lead and Copper Concentrations in Normal and Senile Cataractous Human Lenses

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