Liver cirrhosis and hepatic stellate cells.

The cirrhosis represents the final stage of several chronic hepatic diseases and it is characterized by the presence of fibrosis and morphologic conversion from the normal hepatic architecture into structurally abnormal nodules. In the evolution of the disease there is loss of the normal vascular relationship and portal hypertension. There are also regenerative hepatocellular alterations that become more prominent with the progression of the disease. The liver transplantation continues to be the only therapeutic option in cases of disease in terminal phase. The hepatic stellate cells (HSC) are perisinusoidal cells that store vitamin A and produce growth factors, citocins, prostaglandins and other bioactive substances. They can suffer an activation process that convert them to cells with a phenotype similar to myofibroblasts. When activated, they present increased capacity of proliferation, mobility, contractility and synthesis of collagen and other components of extracellular matrix. They possess cytoplasmic processes adhered to sinusoids and can affect the sinusoidal blood flow. HSC are important in pathogenesis of fibrosis and portal hypertension.