Relative zinc-binding capacity of metallothionein in hepatic cytosols of zinc-injected rats.
In order to determine the zinc-binding capacity of metallothionein in hepatic cytosols of zinc-injected rats, we examined the relationship between zinc contents in cytosols and metallothionein fraction in rat livers. Each rat was injected intraperitoneally once with 0.9 % NaCl or zinc (10, 20, 40 or 60 mg zinc/kg b.w.) and was killed 14 h after injection. The distribution profiles of the hepatic cytosols of zinc-injected rats on a Sephadex G-75 column showed that the increased zinc was attributable to the metallothionein and high molecular weight proteins. Our results demonstrated that 63% of the increased zinc in hepatic cytosols of zinc-injected rats was bound to metallothionein and that 23% of the increased zinc was bound to high molecular weight proteins. These results suggest that the mechanisms of zinc accumulation in rat liver are different from those of cadmium accumulation.
Saito
S
S
Department of Environmental Medicine and Informatics, Graduate School of Environmental Earth Science, Hokkaido University, Sapporo, Japan.
Kojima
Y
Y
D000818:Animals; D001667:Binding, Competitive; D004305:Dose-Response Relationship, Drug; D008099:Liver / Q000378:metabolism*; D008297:Male; D008668:Metallothionein / Q000378:metabolism*; D051381:Rats; D017207:Rats, Sprague-Dawley; D015032:Zinc / Q000378:metabolism* / Q000494:pharmacology*
D008668:Metallothionein; D015032:Zinc