noun, plural: erythropoietins
Erythropoietin is a 46 kD glycoprotein. In adults, it is produced primarily by the interstitial fibroblast cells in the kidneys. The cells are sensitive to low arterial oxygen concentration and will release erythropoietin when oxygen is low (hypoxia). In fetal and perinatal period, the hormone is produced chiefly by the perisinusoidal cells in the liver.
The measurement of this hormone in the bloodstream can indicate bone marrow disorders or kidney disease. Normal levels of erythropoietin are 0 to 19 mU/ml (milliunits per millilitre). Elevated levels can be seen in polycythaemia rubra vera. Lower than normal values are seen in chronic renal failure.
A synthetic version of erythropoietin is made available through recombinant DNA technology. Recombinant human erythropoietin (or erythropoiesis-stimulating agent, ESA) is used therapeutically to treat anemia in medical conditions such as chronic kidney disease and myelodysplasia. It is also being used illegally by athletes as a performance-enhancing drug.
Word origin: poiēt(ḗs) ("maker")