Enzyme leakage due to change of membrane permeability of primary cultured rat hepatocytes treated with various hepatotoxins and its prevention by glycyrrhizin.

Various hepatotoxins were added to the medium of primary cultures of adult rat hepatocytes and the release of the cytosolic enzymes lactic dehydrogenase, glutamic-oxaloacetic and glutamic-pyruvic aminotransferases were measured 24 h later. CCl4 at low concentrations caused dose-dependent release of soluble enzymes into medium without appreciable cytolysis of the hepatocytes. Mitochondrial enzymes were not released under these conditions. At 5 mM CCl4, both soluble and mitochondrial glutamic-oxaloacetic aminotransferase were found in the culture medium. Glycyrrhizin, a triterpenoid glycoside of licorice roots, prevented the enzyme release caused by CCl4.