[Morphological manifestations of compensatory-adaptive processes in the liver during aging].

Light and electron microscopy and morphometry revealed an age-related increase in the average size of hepatocytes and their nuclei in 24- and 30-month-old rats compared to 8-month-old animals, the density of hepatocytes distribution per area unit being decreased. In 24-month-old rats the number of binuclear hepatocytes increased with a subsequent decrease in their number in 30-month-old animals, which accounted for the shift in regeneration processes during ageing to predominantly intracellular one. The number of sinusoidal cells per area unit in three age groups was statistically similar. The results of morphometry and electron microscopy suggest that the compensatory-adaptive processes during hepatocyte ageing were mediated by intracellular regeneration, which led to cellular and nuclear hypertrophy similar to that observed in cells of static population (neurons, cardiomyocytes).