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Archives of Toxicology

, Volume 64, Issue 3, pp 177–180 | Cite as

The Cd-Chelex assay: A new sensitive method to determine metallothionein containing zinc and cadmium

  • Rüdiger Bartsch
  • Dominik Klein
  • Karl H. Summer
Original Articles

Abstract

A rapid and sensitive one-vial procedure to determine metallothionein (MT) containing zinc (Zn) and cadmium (Cd) is described. New features of this Cd-saturation method are: high molecular weight Cd-binding proteins are denatured by treatment with acetonitrile (50% final concentration), and excess of Cd is bound to a cation exchange resin (Chelex-100). With this method, MT has been measured, e.g. in liver of control and zinc- or cadmium-treated rats, in human liver and in cultured human fibroblasts down to absolute amounts of 0.1 μg. The Cd-Chelex assay is 10 times more sensitive than the established Cd-heme assay (Dieter et al. 1986) and therefore is particularly suitable to quantify MT in small tissue samples (e.g., liver biopsies of a few milligrams) and in extrahepatic tissues or cell cultures with low MT concentrations.

Key words

Chelex Metallothionein Cd-saturation assay Zinc Cadmium 

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References

  1. Cai W, Stillman MJ (1988) Metal binding in metallothioneins: competition for cadmium and zinc between Chelex-100 and metal binding sites in metallothionein. Inorg Chim Acta 152: 111–115Google Scholar
  2. Dieter HH, Müller L, Abel J, Summer KH (1986) Determination of Cd-Thionein in biological materials: comparative standard recovery by five current methods using protein nitrogen for standard calibration. Toxicol Appl Pharmacol 85: 380–388PubMedGoogle Scholar
  3. Eaton DL, Toal BF (1982) Evaluation of the Cd/hemoglobin affinity assay for the rapid determination of metallothionein in biological tissues. Toxicol Appl Pharmacol 66: 134–142PubMedGoogle Scholar
  4. Foulkes EC (ed) (1982) Biological roles of metallothionein. Elsevier/North Holland, New YorkGoogle Scholar
  5. Heilmaier HE, Summer KH (1985) Metallothionein content and zinc status in various tissues of rats treated with iodoacetic acid and zinc. Arch Toxicol 56: 247–251PubMedGoogle Scholar
  6. Kägi JHR, Kojima Y (eds) (1987) Metallothionein II. Birkhäuser Verlag, BaselGoogle Scholar
  7. Klauser S, Kägi JHR, Wilson KJ (1983) Characterization of isoprotein patterns in tissue extracts and isolated samples of metallothioneins by reverse-phase high-pressure liquid chromatography. Biochem J 209: 71–80PubMedGoogle Scholar
  8. Lowry OH, Rosebrough NJ, Farr AL, Randall RJ (1951) Protein measurement with the Folin phenol reagent. J Biol Chem 193: 265–275PubMedGoogle Scholar
  9. Nolan CV, Shaikh ZA (1986) Determination of metallothionein in tissues by radioimmunoassay and by cadmium saturation method. Anal Biochem 154: 213–223PubMedGoogle Scholar
  10. Nolan CV, Shaikh ZA (1987) Induction of metallothionein in rat tissues following subchronic exposure to mercury shown by radioimmunoassay. Biol Trace Element Res 12: 419–428Google Scholar
  11. Waalkes MP, Garvey JS, Klaassen CD (1985) Comparison of methods of metallothionein quantification: cadmium radioassay, mercury radioassay, and radioimmunoassay. Toxicol Appl Pharmacol 79: 524–527PubMedGoogle Scholar
  12. Winge DR, Miklossy KA (1982) Domain nature of metallothionein J Biol Chem 257: 3471–3476PubMedGoogle Scholar

Copyright information

© Springer-Verlag 1990

Authors and Affiliations

  • Rüdiger Bartsch
    • 1
  • Dominik Klein
    • 1
  • Karl H. Summer
    • 1
  1. 1.Institut für ToxikologieGesellschaft für Strahlen- und UmweltforschungNeuherbergFRG

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