[Intracellular distribution of a DNA and carminomycin complex]

The complex of the tritium labeled DNA with carminomycin was injected intravenously to mice. Five h after the complex injection the rats were sacrificed. The liver was isolated and homogenized. The cells were consecutively divided into fractions: intercellular liquid, cytoplasm, nuclear juice and chromatin. The content of high-molecular exogenous DNA and the products of its degradation, as well as the quantity of free and DNA bound carminomycin were determined radiometrically and spectrofluorometrically in every of the above fractions. It was found that the carminomycin complex located in the liver remained unchanged for a long time after injection and penetrated into the cell in the form of the complex. In the cytoplasm, the complex disintegrated to liberate carminomycin which penetrated into the nucleus where it was bound to chromatin DNA.