Physiology and pathophysiology of liver inflammation, damage and repair.

The liver is the largest organ of the body. It is located between the portal and the general circulation, between the organs of the gastrointestinal tract and the heart. The main function of the liver is to take up nutrients, to store them, and to provide nutrients to the other organs. At the same time has the liver to take up potentially damaging substances like bacterial products or drugs delivered by the portal blood or microorganisms, which reach the circulation. The liver is not only an important power and sewage treatment plant of the body. In fact, the liver is probably the best example for a cheap recycling system. Both parenchymal and nonparenchymal liver cells participate in the clearance activities. The function of the liver as clearance organ, however, harbors the danger that the substances that should be degraded and/or eliminated lead to tissue damage. Thus, effective defense mechanisms are necessary. Among the nonparenchymal cells Kupffer cells, sinusoidal endothelial cells, and natural killer (NK) lymphocytes exert cellular defense functions for the whole body but also for the liver itself. Furthermore, each cell type of the liver, including the hepatocytes, possesses its own defense apparatus.