[Changes in sphingomyelinase activity, tumor necrosis factor alpha level, and lipid peroxidation rate in the course of development of cholestatic liver injury].

Changes in sphingomyelinase activity, tumor necrosis factor alpha expression, and lipid peroxidation rate in the course of development of cholestatic liver injury have been studied. The same type phase shifts in the parameters analyzed were observed, which included a marked decrease at the early stages of cholestasis (days 3-6) and a pronounced increase at the later stages (days 12-16), i.e., under the conditions of developed pathology. There is a significant positive linear correlation between tumor necrosis factor alpha expression, sphingomyelinase activity, and lipid peroxidation rate during cholestatic injury. The changes detected may reflect balance between the effects of the two major bile components--bilirubin, which is accumulated in the liver at the early stages of cholestasis, and bile acids, whose influence dominates at the later stages of pathologic process. Our results indicate that tumor necrosis factor alpha overexpression, the sphingomyelin cycle activation, and lipid peroxidation intensification may cause apoptosis of hepatocytes at the late stages of cholestasis.