SUBCELLULAR AND INTRANUCLEAR LOCALIZATION OF NP-237(V) IN RAT-LIVER

The present investigation was aimed at establishing the distribution o f Np-237 within the different structures of hepatocytes. Rats were con taminated experimentally by intravenous injection of Np-237 (V) and th e subcellular structures of the liver were separated by ultracentrifug ation. Twenty-four hours after contamination, the nuclear and cytosoli c fractions bound 54 and 32%, respectively, of the total radionuclide. Purification of the nuclei followed by dissociation of the protein co mponents in medium of increasing ionic strength showed a specific bind ing of neptunium to the structural proteins of the nuclear matrix. (C) 1995 by Radiation Research Society