Effect of Vitamin B₁₂ on the Synthesis of Protein and Nucleic Acids in the Liver

Abstract

IT is known that the cytoplasm content of the liver is determined by protein nutrition¹, and recently vitamin B₁₂ has been shown to promote amino-acid assimilation². A decrease in liver basophile cells (attributable to ribonucleic acid) is observed in rats deficient in vitamin B₁₂³. The vitamin also protects against hepatic damage during carbon tetrachloride intoxication, which causes a considerable reduction in the ribonucleic acid content of the liver⁴. All these findings suggest that vitamin B₁₂ may influence protein as well as nucleic acid metabolism in the liver. We have sought direct experimental evidence for this in studies based on the regeneration of the labile liver cytoplasmic proteins in the rat following a brief fast. The results of a typical experiment are presented here.