Erythropoietin

(EPO); (pronounced, ah-rith-ro-poy-tin, and abbreviated, EPO); a protein hormone that enhances erythropoiesis by stimulating formation of proerythroblasts and release of reticulocytes from bone marrow; it is secreted by the kidney and possibly by other tissues

Description
EPO is released into the blood stream and binds with receptors in the bone marrow, where it stimulates the production of erythrocytes. Therapeutically, EPO is used to treat certain forms of anemia (e.g., due to chronic kidney failure, cancer, myeloma) as well as in orthopedic surgery and intensive care medicine as an alternative to blood transfusion. EPO accelerates erythrocyte production, thus increasing the hematocrit and oxygen carrying capacity. It is therefore a banned substance in sports competitions.