Hepatic regeneration and metabolism after partial hepatectomy in normal rats: effects of insulin therapy.

The effect of insulin therapy on liver regeneration has been studied in normal fed rats 12, 24 and 48 h after partial hepatectomy. Dry weight of regenerating liver increased between 12 and 48 h after partial hepatectomy and was unaffected by insulin therapy. [6-3H] Thymidine uptake peaked at 24-h (24.7 +/- 2.4% of total liver cells) and insulin treatment had no additional effect. At 12-h after partial hepatectomy, hepatic [ATP] was decreased 15%, while [ADP] and [AMP] were increased 47% and 83% respectively compared with sham-operated animals. Partial hepatectomy also caused an increase in hepatic [triglyceride], a decrease in hepatic [glycogen] and an increase in the levels of glucose and several glycolytic intermediates. The hepatic redox ratios, [lactate]:[pyruvate] and [3-hydroxybutyrate]:[acetoacetate], were elevated. Insulin therapy had only minor effects on hepatic adenine nucleotide levels, intermediary metabolite concentrations or intrahepatic redox ratios after partial hepatectomy. These findings suggest a decreased hepatic intracellular energy state in regenerating liver; insulin therapy in normal rats does not influence this metabolic change nor the regenerative response.