Intestinal metallothionein and the mutual antagonism between copper and zinc in the rat

doi:10.1016/S0162-0134(00)80054-9

Journal of Inorganic Biochemistry

Volume 11, Issue 1, 1979, Pages 57-66

https://doi.org/10.1016/S0162-0134(00)80054-9 Get rights and content

Abstract

A study has been made of the mechanism of the mutual antagonism between copper and zinc in rats. Dietary zinc concentrations of up to 450 mg/kg had no effect on intestinal ⁶⁴Cu absorption but 900 mg/kg caused a 40% reduction. This was associated with an increase in the mucosal uptake of ⁶⁴Cu in the small intestine. This occurred mainly in the form of metallothionein and it appeared that copper displaced zinc from the protein after its synthesis had been induced by zinc.

The intestinal absorption of ⁶⁵Zn was decreased by 20% when the dietary copper intake was increased from 3 to 24 mg/kg. Further increases in copper intake to 300 mg/kg did not cause any additional decrease in ⁶⁵Zn absorption or any change in the association of intestinal ⁶⁵Zn with metallothionein. Concentrations of this protein in the intestinal mucosa were not influenced by dietary copper intake.

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Intestinal metallothionein and the mutual antagonism between copper and zinc in the rat

Abstract

J. Nutr.

J. Nutr.

J. Nutr.

J. Nutr.

Biochem. Biophys. Res. Comm.

Biochem. Biophys. Res. Comm.

J. Nutr.

Life Sci.

J. Nutr.

Life Sci.

Bioinorg. Chem.

Quart. Rev. Biophys.

Proc. Soc. Exp. Biol. Med.