1. (+)-Octanoylcarnitine, a potent inhibitor of fatty acid oxidation, was infused intraportally into rabbits after 70% hepatectomy, and its effects on the rate of deoxyribonucleic acid (DNA) synthesis were examined.
2. The rate of DNA synthesis was markedly enhanced 48 h after hepatectomy. At this time, synthesis was decreased significantly by (+)-octanoylcarnitine.
3. It is suggested that fatty acid oxidation contributes to enhanced hepatic regeneration by elevating the decreased energy charge level [(ATP + 0.5ADP)/(ATP + ADP + AMP)] of the remnant liver.