Abstract
Compared with normally fed animals, rats fed on a low-protein diet for 3 days exhibit a considerable delay in DNA synthesis after partial hepatectomy. In the regenerating livers of these animals the timing of the 1st peak of ornithine decarboxylase activity is not altered and the 2nd peak of enzyme activity is delayed by a few hours, but polyamine concentrations are similar to those of normally fed rats. Regardless of the possible effect of polyamines on DNA synthesis, the time course of ornithine decarboxylase activity appears to be independent of the onset of DNA replication in regenerating livers.