Abstract
Tissue and organ distribution of radioactive carbon from 14C-labeled tryptophan in the mouse was studied by whole-body autoradiography and biochemical analysis. The mice injected intravenously with L-[side chain-3-14C]tryptophan were sacrificed at various intervals. Examination of autoradiographs disclosed that the injected 14C-tryptophan was rapidly taken up from the blood by the organs. The radioactivity in the pancreas was the highest and predominant throughout the intervals after injection in this investigation.
The comparative values among radioactivity in various organs estimated by a liquid scintillation counter were consistent with those obtained from whole-body autoradiographs. Radioactivity in the acid-insoluble fractions was increased with time in all organs examined. High-performance liquid chromatography of the acid-soluble fractions disclosed radioactive tryptophan and alanine in the blood, liver, kidney and small intestine, while radioactive alanine was not detected in the brain.
