Final answer:
Erythropoietin-stimulating agents (ESAs) are synthetic forms of EPO that are used to treat certain anemias by stimulating red blood cell production, improving oxygen carriage. They carry risks such as increased blood viscosity and potential for thrombotic events, so their use is carefully managed. ESAs are also known as a banned performance-enhancing substance in athletics.
Step-by-step explanation:
Erythropoietin-stimulating agents (ESAs) are important drugs used in medical treatment to manage anemia, particularly those that are associated with chronic kidney disease, certain cancers, and other medical conditions where increased red blood cell production is beneficial. Erythropoietin (EPO), a glycoprotein hormone, is naturally secreted by interstitial fibroblast cells in the kidneys when oxygen levels are low. ESAs are synthetic forms of EPO that are designed to mimic the action of the natural hormone, thereby stimulating the production of red blood cells (erythrocytes) in the bone marrow. This process can help increase the hemoglobin levels and improve the oxygen-carrying capacity of the blood.
However, these agents are not without risks. The use of ESAs can lead to increased blood viscosity, which makes it more difficult for blood to circulate and can contribute to an elevated risk of thrombotic events, like heart attacks and strokes. Therefore, the prescription of ESAs is carefully tailored and monitored by healthcare professionals to ensure patient safety.
Outside of medical settings, synthetic EPO is known to be used by athletes as a performance-enhancing substance, commonly referred to as blood doping, to increase endurance by boosting the red blood cell count and consequently the oxygen delivery to muscles. This practice is banned in most organized sports due to health risks and its unethical advantage in performance enhancement.