The Source of Vitality
Making Red Blood CellsAlong with their many other functions, your kidneys also regulate red blood cell production. Having enough red blood cells is very important, because they transport the vital molecule that fuels our life processes, oxygen, from the lungs to the all the different cells and tissues that require it.
The kidneys measure oxygen levels in the blood that streams through the glomerular capillaries. When they detect below-normal oxygen levels, the kidneys release the hormone erythropoietin (EPO). The kidneys make 90% of the EPO in the body. READ MORE
Most EPO production takes place in the renal cortex, in the upper portion of the kidneys. EPO is produced mainly by peritubular fibroblasts (specialized cells that produce collagen and other materials) of the renal cortex. The peritubular capillaries travel alongside the nephrons.
EPO travels from your kidneys to your bone marrow, where about 95% of blood cells are made. There, EPO binds to receptors in the walls of stem cells. This triggers a series of events inside the stem cells that instructs their DNA to transform them into red blood cells. Many cells can result from one stem cell. In fact, a single stem cell might differentiate into as many as 32 red blood cells. LESS
Making Up for Lost EPOPeople with kidney failure become anemic because their kidneys no longer make sufficient quantities of EPO to stimulate red blood cell production in the bone marrow. Anemia is a disorder in which there are not enough red blood cells in the blood, or there isn’t enough normal hemoglobin in the red blood cells. READ MORE
Fortunately, a synthetic version of EPO is available that can be taken through subcutaneous (under the skin) injection, several times a week. Longer-acting EPO may also be given intravenously every other week. LESS