Studies on the Site of Synthesis of Transcobalamin-II ∗

Abstract

Summary

The liver, kidneys, and stomach were studied to determine the site of trans-cobalamin-II synthesis. The kidney is not the site since total nephrectomy had no effect on the reappearance of TC-II after saturation of TC-II with B₁₂. Total gastrectomy also had little effect on TC-II levels or rate of synthesis. The liver proved to be the site of TC-II synthesis because of the following findings. Destruction of liver with carbon tetrachloride resulted in a decrease of serum TC-II. Unsaturated TC-II in the blood after saturation with cyanocobalamin was markedly low in the carbon tetrachloride treated animals. TC-II was shown to be synthesized by the perfused rat liver.