Fate of intraperitoneally injected liver metallothionein in rat kidney.

Abstract

Isolated rat liver metallothionein was injected i.p. into female rats to find whether the injected metallothionein was recovered from the kidneys with as high Cu content as in the case of rat kidney metallothionein induced by exposure to inorganic Cd ion. The distribution patterns of Cd and Zn among protein fractions in the kidney supernatants changed dramatically within 1 day after the injection. The changes were explained by the degradation and resynthesis of the injected metallothionein in the kidneys. Cu was not a major metal in any metallothionein fractions obtained from the kidney supernatants. This is in marked contrast to Cd ion-exposed rat kidney metallothionein. The relationships between the selective and profound toxicity of the injected metallothionein to the tubular lining cells and the changes of the chemical forms of Cd were also discussed.