Studies on the Bone Marrow Function and the Iron Metabolism Part 1. On the Movement of Stored Iron in Accordance with the Bone Marrow Function

The relationship between stored iron and hematopoietic function of the bono marrow was studied in rabbits under various conditions by means of radioactive iron (Fe(55)). The quantitative fractionation of tissue iron was performed according to the method described by Yoneyama and Konno. In normal rabbits, radioactive iron, intravenously injected in tracer amounts, distributed in PⅠ (probably contains hemosiderin) as well as PⅡ (proved to have come really from ferritin) in an almost epual amount. By mobilization and utilization, however, a preponderance of PⅡ over PⅠ was recognized. In rabbits with anemia due to blood loss, the movement of administered radioactive iron was accelerated and specifc activity of PⅢ in bone marrow markedly increased. In rabbits suffered from disturbances on hematopoietie function, such as X-ray irradiation and collargol injection, on the contrary, the movement of iron was slow and PⅢ in bone marrow came to the retetion. In rabbits suffered from X-ray irradiation after bleeding, it was revealed that PⅢ in bone marrow was most available for heme synthesis in three fractions. In accordance with the procedures which caused the hematopoietic disturbances, the distribution of non-hemin iron in the spleen showed the same pattern as in bone marrow, i.e., at 24 hours after injection of radioactive iron PⅢ was markedly increased and PⅡ was decreased.