Abstract
An energy requirement for support of macromolecule synthesis is well realized. However, although a number of works have been made to clarify the close correlation between polynucleotide synthesis and energy supply, no convincing evidence has been provided for an important role of mitochondrial metabolism in the regenerating process. Most studies on liver regeneration have been conducted on partial hepatectomized rats, but in view of alteration in energy metabolism which may occur soon after hepatectomy, the hepatectomized rats appear to be unsuitable for studying energy metabolism in the regenerating process. Consequently, we have selected the ligation method of a portal vein branch in rabbits. This method is not only a milder treatment than hepatectomy, but offers advantages that both regeneration and atrophy processes can be followed to test for a possible humoral mechanism and that enhancement in the rate of DNA synthesis is very similar to the one which has been increased by subtotal hepatectomy.
In this study, it has been suggested that (1) a highly integrated stimulation of mitochondrial energy-generating capacity precedes DNA synthesis and (2) alteration of the quantitative balance between an available factor in portal blood and respiratory assemblies induces enhancement or depression of mitochondrial metabolism, resulting in regeneration and atrophy, respectively.