6th ESACP Congress, Heidelberg, April 7-11, 1999

A156
ULTRASTRUCTURAL AND IMMUNOHISTOCHEMICAL EVODENCE OF THE HEPATIC STELLATE CELL PROLIFERATION AND INCREASED FUNCTIONAL ACTIVITY IN CHRONIC LIVER DISEASE
Zalcmane V, Groma V

Medical Academy of Lativia, Riga, Latvia

An increased functional activity and proliferation of the hepatic stellate cells in the liver biopsies of the patients with cirrhosis and chronic hepatitis B and C have been demonstrated in this study by use of immunohistochemistry and electron microscopy. Both morphological methods provided a strong evidence that proliferation of the hepatic stellate cells is associated with the phenotypic changes of these cells. These ultrastructural changes include a decrease of an amount of vitamin A- containing lipid inclusions, an increase of rough endoplasmic reticulum and appearance of abundant intracellular microfilaments near the plasma membrane. There was a marked ultrastructural heterogeneity in the population of the hepatic stellate cells observed in the present study. During hepatic injury in case of chronic liver disease some of the above mentioned cells transformed into the myofibroblast-like cells. An increase of extracellular matrix, including collagen microfibrills, has been noticed near the myofibroblast like cell surface. Cytoplasm of these cells contained numerous actin microfilaments that have been demonstrated also immunohistochemically. A marked proliferation of stellate and myofibroblastic cells has been observed in the close proximity to the damaged hepatocytes.