A flow cytofluorometric study on age-dependent ploidy class changes in mouse hepatocyte nuclei.

To quantitate the age-dependent hyperploidization of mouse hepatic cell nuclei, a cytophotometric study using FACS III was performed. The isolated nuclei from the liver of C57BL/6CrSlc mice at various ages were stained with chromomycin A3. The fraction of polyploid nuclei was increased with age and invariably greater in male than in female animals of corresponding ages. The highest ploidy class observed was 16C, but from the analysis of polyploidization ratio, increase in 4C and 8C nuclei was considered to be the characteristic of the age-related change.