Urea excretion, galactose elimination, and aminopyrine disappearance during normal liver regeneration after partial...

After removal of 70% of normal rat liver, liver weight was 37% of control at 3 1/2 hours and 49% at 24 hours. Urea formation per gram liver after an NH4+ load and galactose elimination per gram liver were well-preserved during this early posthepatectomy period. At 46 hours after removal, galactose elimination was transiently less than would be expected from liver weight. The aminopyrine disappearance rate fell to 50% to 63% of control values until 72 hours, when it decreased further to 43%, disproportionately less than liver weight. The disappearance rate per gram liver at this time was 63% of control. Serum bile acid concentration increased 17-fold by 24 hours, and was five times that of control concentration at 72 hours. Comparisons of these four measures and six other in vivo measures of function previously reported permitted a segregation of the livers into two groups according to liver function after hepatectomy: those that were disproportionately preserved or were proportional to the amount of liver present, and those that were disproportionately reduced in relation to liver weight. Four additional measurements reported in isolated perfused livers after hepatectomy were similarly segregated. It appears that those liver functions that most closely reflect cellular growth or associated changes in liver blood flow are preserved, whereas those that are possibly more specialized and differentiated are depressed during regeneration.