Functional regeneration in liver of old rats after partial hepatectomy

This study suggests that changes in liver protein metabolism occurring with age are not due to changes in the genome. Regenerating rat liver in old animals has regained functional properties of young rat liver.Specifically albumin synthesis, which is elevated in old animals, returns to young rat levels in old rats for several weeks after partial hepatectomy. Both in vivo and in vitro studies support this evidence. Old rat liver ferritin also undergoes changes in regenerating liver. The amount of ferritin iron/g liver falls to one half, the amount of iron/mg ferritin protein drops, but the amount of ferritin protein/g liver remains constant in regenerated old rat liver. The half-life of ferritin in regenerated old rat liver (2·3 days) is much shorter than in old rat liver controls (3·9 days) and approaches that of young rat liver ferritin (2·1 days).Determinations were done at a time when liver weight had been fully restored following removal of 67 per cent of the liver. Functional properties of old rat liver are restored by 12 weeks after partial hepatectomy.