Reticulocyte Size and Erythropoietic Stimulation

Abstract

The size distribution of peripheral red blood cells of rats recovering from phenylhydrazine anemia is reported. Reticulocytes produced during the first burst of active erythroid regeneration are as much as twice the normal size; degree of macrocytosis is related to the severity of the anemia. The initial crop of oversized cells is replaced by successive crops of reticulocytes of more normal size. It is suggested that separation of reticulocytes by centrifugation depends on their density, which is determined primarily by the MCHC.