Analysis of the postnatal growth of the mouse liver by estimating the hepatocyte count, their weight and ploidy

Changes in the total number of hepatocytes, their distribution by the ploidy classes, as well as changes in the protein content of the cells were studied in 0.5-6 month old mice. The data obtained made it possible to estimate quantitatively the contribution of different growth components: increase in cell number, hypertrophy and polyploidization of cells, to the total increase of the liver mass. From 2 weeks to 1 month, the liver mass is increased via polyploidization (by 70%) and hypertrophy (by 30%). From 1 to 2 months, the liver mass increases due to hyperplasia (by 65%) and polyploidization (35%). After 2 months, the liver growth is practically terminated. The calculated equivalent mass of the liver, i. e. derivative of all three growth components, coincides fairly well with the factual changes in the liver mass.