Humoral Regulation of Erythropoiesis. Xi. the Pattern of Response to Specific Therapy in Iron Deficiency Anemia.

I NITIALLY, macrocytic red cells with a shortened life span are produced in response to intense erythropoietic stimulation, e.g., in phenyihydrazineinduced anemia, severe hlocd loss, exposure to hypoxia or the administration of erythropoietin.1 We have postulated that these macrocytes result from a shortening of the interval between differentiation of stem cells and emergence of reticulocytes together with skipping of divisions in the erythroid compartment.13 In severe iron deficiency anemia, an intense erythroid stimulation may be present but microcytes are produced. Correction of the iron deficiency in the presence of this intense erythroid stimulation might, therefore, result in the production of macrocytes. This thesis was tested in human beings and rats with iron deficiency anemia.