Abstract
The distribution in the mouse of Se(75) after injection of Se(75) sodium selenite was studied by autoradiography of sagittal whole-body sections. The animals were killed at various times, from 5 minutes to 8 days, after a single intravenous injection. The distribution was characterized by a high blood level of selenium during the whole observation period. The highest concentration of selenium soon after the injection was found in the liver, heart, kidney and adrenal cortex. Eight days after the injection the highest concentration was seen in the liver and the kidney. The selenium penetrated the placenta, but the uptake was much lower in the fetuses than in the maternal tissue.