Automated karyometry of hepatocytes during experimental liver carcinogenesis in normally - fed and protein - deficient rats
Abstract
Karyometric results, with stereological sphere unfoldings, from rat liver hepatocytic nuclei, have been obtained after an experimental carcinogenesis (Farber) protocol. The rats were protein deficient, or 20% protein fed. A special image analysis algorithm for the IBAS (Kontron) has been used. The non-parametric unfolding method uses profile area classes. Some difficulties were encountered in the interpretation of the karyometric results. The positioning of the diploid and tetraploid peaks changes in normal animals with age. Some guesses can nevertheless be made at ploidy values. Larger nuclei are observed at 4 months after the onset of the protocol in protein-deficient treated animals. At 5 and 7 months, practically only diploid-sized nuclei are found in treated animals. The results are consistent with a possible early polyploidization during oncogenesis, followed by a re-diploidization. The difficulties in interpreting some histograms show that more studies should be done, and notably comparisons with DNA histograms on smears or by cytoflow.