When you get a cut or abrasion that penetrates your skin, you may bleed for a little while. But before long, the bleeding slows and then stops as a scab begins to form. Your body's remarkable ability to recover from a flesh wound begins with the coagulation of blood platelets formed from amino acids.
Amino Acids
Amino acids are the building blocks of proteins that become part of your body's structures. They also play important roles as intermediaries in metabolism. There are 20 amino acids. Ten of these amino acids your body makes; they are called "non-essential." Ten must come from food; they are called "essential." Because your body does not store amino acids for future use, you must ingest them on a regular basis. If you are deficient in even one essential amino acid, your body's muscle and tissue protein may begin to degrade. Amino acids are important components in blood cells, and they are essential to the formation of blood platelets.
Platelets
Platelets, also called "thrombocytes," are partial cells without a nucleus found in blood. Platelets work with clotting chemicals in blood to plug holes in vascular walls caused by wounds. A normal platelet count is 150,000 to 350,000 per microliter of blood, but because they are only about 20 percent the diameter of red blood cells, they make up only a small amount of total blood volume, according to the University of Oklahoma Health Sciences Center. Platelets are produced in response to a stimulus from a hormone called "thrombopoietin," or TPO, a protein made up of 332 amino acids.
TPO
Blood platelets are formed in bone marrow, as are red and white blood cells, and have a lifespan of nine to 10 days. Platelets come from the megakaryocytes, the large bone marrow cells. TPO stimulates precursor cells in the bone marrow to differentiate into megakaryocytes. As megakaryocytes grow larger, they eventually go through a fragmentation phase where over 1,000 platelets are released. Circulating TPO levels rise and fall in response to platelet counts, increasing when more platelets are needed.
Factors Causing Platelet Dysfunction
Certain medical conditions can cause dysfunctions in platelet production. When your body makes too few or too little platelets, you may have problems with excessive bleeding or too much clotting. The most common platelet disorder comes from aspirin, according to the University of Oklahoma Medical Center. Aspirin blocks a step in the process of clotting that enables platelets to stick together. While aspirin may be helpful for individuals with heart disease in whom excessive clotting could block arteries, it can be lethal in those who are at risk for excessive bleeding.
References
- Palomar Community College: Blood Components; Dennis O'Neil; Aug. 19, 2011
- University of Arizona Biology Project: The Chemistry of Amino Acids; Sept. 30, 2003
- University of Oklahoma Health Sciences Center: Platelets; James N. George; 2007
- Kimball's Biology Pages: Hormones of the Liver; John W. Kimball, Ph.D.; 2011
Member Comments