Studies on reticuloendothelial system and hematopoiesis. II. A study on the morphology and function of erythroblastic islet

1. For the purpose to clarify the role of reticuloendothelial cells in the center of erythroblastic islet, the medullary and extramedullary erythropoietic foci in convalescence of phenylhydrazine arternia were observed by light and electron microscopies, and the mode of development of anemia in rabbit having blocked RES. 2. Light microscopic observations revealed the stimulated formation of erythroblastic islet in phenylhydrazine anemia. Electron microscopic observations revealed the rhopheocytotic vesicles in the membrane of erythroblast, some of which contained ferritin particles. 3. Repeated India ink injections induced anemia with RES damage by being heavily laden with soot particles. Color index of these animals was not reduced to the state of hypochromic anemia. Anemia is due to the damage of erythroidcell reproduction, but not due to the disturbed hemoglobin metabolism by the inhibited iron uptake. 4. From the results obtained the author concludes that the role of reticuloendothelial cell in islet is not to transfer ferritin to erythroblast but the reproduction of erythroid cells.