Some Effects of Continued Protein Deprivation,with and without Methionine Supplementation,on Intracellular Liver Components. ∗

Summary

The intracellular distribution of nitrogen and nucleic acids in the livers of rats fed a diet free of protein for 5 weeks was found to be similar to that previously observed in rats subsisting on the same diet for 3 weeks, although the changes from control values were of greater magnitude in the case of the animals depleted for the longer period of time.

The inclusion of 1% DL-methionine in the protein-free diet had no appreciable effect in protecting the liver from the observed changes due to protein depletion except in partially preventing the increase of PNA in the residual cytoplasmic fraction. It is noted that the changes encountered in the intracellular distribution of nitrogen and nucleic acids in the livers of protein-deficient animals fall into the same pattern as the changes which have been found to obtain in the livers of precancerous and cancerous animals.

The authors are indebted to Dr. Maurice Ogur of Brooklyn College foro making available to them the details of the method for the extraction of nucleic acids prior to publication.