Which hormone produced by the kidneys is responsible for triggering red blood cell production?

The hormone responsible for triggering red blood cell production is erythropoietin, which is produced by the kidneys. When oxygen levels in the blood are low, the kidneys secrete erythropoietin into the bloodstream. This hormone stimulates the bone marrow to increase the production of red blood cells, enhancing the body’s ability to transport oxygen. Erythropoietin plays a critical role in regulating red blood cell levels and is particularly important in individuals with chronic kidney disease, where production may be impaired.

Calcitriol, although essential for calcium metabolism and bone health, is not directly involved in red blood cell production. Aldosterone primarily regulates sodium and potassium levels and blood pressure, while renin is involved in regulating blood pressure through the renin-angiotensin-aldosterone system. None of these hormones directly stimulate red blood cell production in the way that erythropoietin does.