Kinetics
- Platelets are produced in blood cell formation (thrombopoiesis) in bone marrow, by budding off from megakaryocytes.
- The physiological range for platelets is (150–400)×109 per liter.
- Around 1011 platelets are produced each day by an average healthy adult.
- The lifespan of circulating platelets is 5 to 9 days.
- Megakaryocyte and platelet production is regulated by thrombopoietin, a hormone usually produced by the liver and kidneys.
- Each megakaryocyte produces between 5,000 and 10,000 platelets.
- Old platelets are destroyed by phagocytosis in the spleen and by Kupffer cells in the liver.
- Reserve platelets are stored in the spleen, and are released when needed by sympathetically induced splenic contraction.
Read more about this topic: Platelet