Activation of blood platelets in chronic hepatitis and liver cirrhosis P-selectin expression on blood platelets and secretory activity of beta-thromboglobulin and platelet factor-4.

摘要

BACKGROUND/AIMS: Blood platelets are cells that quite often undergo damage in chronic liver diseases. Endotoxemia and hyperkinetic circulation influence platelets in an active manner. The role of platelets in the development of hepatitis and liver fibrosis is speculative. The aim of the study was to determine the influence of chronic liver diseases on platelets morphologic parameters, their secretory activity and P-selectin expression. METHODOLOGY: The examination was completed in the group of 29 patients with chronic hepatitis and 27 with liver cirrhosis of postinflammatory etiology (HBV, HCV). Liver biopsies were carried out in all patients. Thirty-two healthy individuals were the control group. Platelets morphological parameters (number, volume, platelet crit, micro- and macrothrombocyte fraction) were estimated. beta-thromboglobulin concentration and platelet factor 4 in blood serum as well as P-selectin expression on resting platelets and after thrombin activation were also examined. RESULTS: Number, volume, and platelet crit decreased with the advancement of a liver disease. Megathrombocyte fraction increased inversely with the severity of liver damage. The concentration of beta-thromboglobulin and platelet factor 4 alpha-granule contents in blood serum was higher 2- and 7-times, respectively than in healthy controls. P-selectin expression on resting platelets was considerably higher. After stimulation with thrombin, P-selectin expression was equal (chronic hepatitis) or higher (liver cirrhosis) than in the control. CONCLUSIONS: There are changes of platelet morphological parameters, with accompanying megathrombocyte fraction increase that occur in chronic liver diseases. Thrombocytes in chronic liver diseases and liver cirrhosis are more activated. Platelet sensitivity to stimuli in these ailments is higher (liver cirrhosis) than in the healthy controls.