An autoradiographic study on the distribution of 63NiCl2 in mice.

The distribution of 63NiCl2 in mice was studied by autoradiography. A localization of radioactivity was found in the kidneys, the lungs, and the brain and spinal cord. The cartilages, the connective tissues, the skin and the epithelium of the forestomach also showed an uptake of radioactivity. In the kidney, 63Ni(II) was present at all the survival intervals (five minutes to three weeks) in areas of the cortex, probably corresponding to the distal convoluted tubuli. In the lung, radioactivity occurred in the parenchyma shortly after the administration of 63Ni(II) and was retained throughout the observational period three weeks. In the brain and spinal cord, a retention of radioactivity was obvious 10 days and three weeks after administration of 63NiCl2. In cartilage, a high level of 63Ni(II) was present up to 24 hours, while in connective tissues there was a high initial radioactivity, followed by a constant decrease during the seven hours after the administration of 63NiCl2. An uptake of 63Ni(II) in cartilage and skin was also seen when tissue sections of non-treated mice were incubated in solutions containing 63NiCl2. The chondroitin sulphate of cartilage and the keratin of skin have cation-binding properties which may explain the binding of 63Ni(II) in these tissues.