According to the Centers for Disease Control and Prevention, 27,555 people died from chronic liver disease in 2006. The liver is a very important organ, with more than 200 functions. Thus, any disorder that causes severe liver damage is life-threatening. The liver can repair itself to a limited extent. But, if the blood flow within the liver is not restored and fully functional, the liver will not recover.
Synthesis of Bile
The liver is responsible for making a substance called bile, which helps break up fats. It is made out of water, bilirubin (from the hemoglobin of red blood cells), cholesterol, lipids and bile salts. As explained by Mandana Khalili, M.D., associate professor of medicine at the University of California, in "Pathophysiology of Disease," bile leaves the liver and goes into the small intestines. It can also be concentrated and stored in the gall bladder for future use.
Synthesis of Plasma Proteins
The liver makes and releases most of the proteins that are found in plasma. Albumin is the most important plasma protein made by the liver, according to Kim Barrett, Ph.D., professor in the Department of Medicine at the University of California in "Ganong's Review of Medical Physiology." One of its tasks is to carry various substances around in the bloodstream, such as bilirubin, fats, steroids, hormones and calcium. The liver also makes clotting factors and acute-phase reactants. Clotting factors are proteins that are mandatory in the formation of blood clots. Acute-phase reactants are proteins that are part of the body's response to injury.
Removal of Toxins
Some toxins, or poisons, are stored by the liver inside of fats. In this way, they cannot do any harm. Other toxins are broken down and secreted into the bile. They will leave the liver via the bile, go to the intestines and then leave the body all together.
Storage of Iron
Large amounts of iron are toxic. So, when old or abnormal red blood cells are broken down and recycled by the spleen, the iron in those red blood cells is joined to a plasma protein called transferrin. Red blood cells that are just being formed in the bone marrow will use the transferrins and iron. Any extra transferrins will have their iron removed in the liver. The liver will then join the iron to ferritin. Dr. Khalili writes in "Pathophysiology of Disease" that this is how the liver builds a storage supply of iron. When the body needs iron, it is there in the liver, ready to be used. At the same time, the liver protects the iron from any microorganisms and protects the body from the toxic effects of high levels of iron.
Metabolism of Carbohydrates
Dr. Barrett describes the "glucose buffer function" of the liver in "Ganong's Review of Medical Physiology." Whenever the blood glucose levels drop, the liver will break down the stored glucose (called glycogen) and release that glucose into the bloodstream. The liver will also make glucose, if necessary. When the levels increase after a meal, the liver takes glucose out of the bloodstream, stores it as glycogen or uses it to make fats. Fats are also stored.
References
- Centers for Disease Control and Prevention: Chronic Liver Disease or Cirrhosis
- "Ganong's Review of Medical Physiology"; Kim Barrett, Ph.D., Susan Barman, Ph.D. et al.; 2010
- "Pathophysiology of Disease: An Introduction to Clinical Medicine"; Stephen McPhee, M.D., Gary Hammer, M.D., Ph.D.; 2010
