Erythropoietin acts by binding to the specific erythropoietin receptor (EpoR).
Erythropoietin production is stimulated by the reduction of oxygen in the renal arteries. Erythropoietin produced in the kidney/bone marrow system stimulates stem cells in the bone marrow to increase production of erythrocytes (red blood cells). The role of paracrine erythropoietin in the brain and uterus is not fully elucidated.
The gene which encodes Erythropoietin production was cloned in 1985 and has been succesfully implanted in guinea pigs in order to produce artificial Erythropoietin in the form of Epoetin.
Another substance in the same class is darbepoetin.