High-performance size-exclusion chromatography of /sup 63/Ni-constituents in renal cytosol and microsomes from /sup 63/NiCl/sub 2/-treated rats

Fractionations of /sup 63/Ni-constituents were performed by high-performance size-exclusion chromatography upon samples of renal cytosol and washed renal microsomes from rats that were killed 1 h after an im injection of /sup 63/NiCl2. Chromatography of renal cytosol on TSK-GEL SW-2000 and SW-3000 separated /sup 63/Ni into six fractions. The largest component (Fraction F) contained approximately 80% of cytosolic /sup 63/Ni. Since Fraction F was eluted near the total permeation volume of SW-2000 columns and beyond the total permeation volume of SW-3000 columns, its molecular weight could not be reliably estimated. The other components, which comprised collectively the remaining 20% of cytosolic /sup 63/Ni, had apparent molecular weights of 168,000 (Fraction A), 84,000 (Fraction B), 51,000 (Fraction C), 24,000 (Fraction D), and approximately 10,000 (Fraction E). Solubilized washed microsomes from kidneys of /sup 63/NiCl2-treated rats contained /sup 63/Ni in five components with elution profiles and /sup 63/Ni-contents that resembled Fractions A, B, D, E, and F of renal cytosol, based upon chromatography on SW-3000 columns. This study provides a rapid, convenient, and reproducible technique to fractionate /sup 63/Ni-components in tissue extracts, and it demonstrates in vivo binding of /sup 63/Ni to several constituents of renal cytosol and microsomes from /sup 63/NiCl2-treatedmore » rats.« less