Binding of 63Ni by cellular constituents in some tissues of mice after the administration of 63NiCl2 and 63Ni(CO)4.

One and 24 hours after the administration of 63NiCl2 and 63Ni(CO)4 to mice 63Ni was present in association with both particulate and soluble cellular constituents in the lung, liver and kidney. After disruption of the cellular organells by sonication, a considerable part of the 63Ni was still bound to the cellular fragments. Sephadex G-75 chromatography of the cytosol of the lung showed that the largest proportion of 63Ni was eluted in the void volume and a smaller proportion was present in the salt volume. In the kidney, the proportions were reversed. Twentyfour hours after the injection of 63NiCl2 an intermediate 63Ni-containing peak, with an estimated molecular weight of about 30,000, was found in the lung and the kidney. In the liver of 63 NiCl2-injected mice, most of the nickel was recovered in the void volume, a lesser amount in the salt volume. There was no evidence that 63Ni was bound to metallothionein (induced by Cd-pretreatment) or to superoxide dismutase in the studied tissues. Pretreatments with non-labelled NiCl2 did not alter the elution profiles. In serum, most 63Ni was present in association with albumin. Gel-chromatograms of red blood-cell hemolysates from 63Ni(CO)4-injected mice showed 63Ni at an elution volume corresponding to hemoglobin, but 63Ni-binding ligands with higher and lower molecular weights were also present.