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Objective: To observe the effects of tetramethylpyrazine (TMP) on tissue factor (TF) expression induced by thrombin in human umbilical vein endothelium derived cell line ECV304., Methods: The changes in the total cellular procoagulant activity (PCA) of ECV304 cells exposed to thrombin were observed with one-stage clotting assay. TF mRNA expression in the exposed cells was examined using semi-quantitative reverse transcription-polymerase chain reaction (RT-PCR)., Results: ECV304 cells stimulated with increasing concentrations of thrombin (1.25-20 U/ml) showed a gradual increase of PCA (r=0.9602, P<0.01). The application of FVII-deficient plasma and the monoclonal antibody of TF confirmed that the PCA of the cells mediated by TF activity. TMP at 125-1000 microg/ml alone did not affect TF expression in ECV304 cells (P>0.20), TMP administered 30 min prior to thrombin exposure showed a significant concentration-dependent inhibitory effect on the increments of PCA (r=-0.9644, P<0.01) and TF mRNA expression (r=-0.9576, P<0.05) in ECV304 cells, and 1000 microg/ml TMP produced the strongest effect. In ECV304 cells stimulated with thrombin for 4, 6, 8, 10 and 12 h, TMP administration significantly inhibited the thrombin-induced PCA, and the effect was especially obvious at 8 h following thrombin exposure (P<0.05)., Conclusion: Thrombin induces TF expression in vascular endothelial cells, and this effect can be inhibited by TMP at the mRNA level.

Aim: To study the plasma des-gamma-carboxy protein C activity, antigen and prothrombin levels in patients with liver diseases and their clinical significance., Methods: Plasma protein C activity (PC:C) was detected by chromogenic assay and antigen (PC:Ag) and des-gamma-carboxy protein C (DCPC) were detected by ELISA. Total prothrombin and unabsorbed prothrombin in plasma were detected by ecarin chromogenic assay., Results: Compared with the control, the levels of PC:C and PC:Ag in patients with hepatocellular carcinoma (HCC) and liver cirrhosis (LC) were lower (PC:C: 104.65+/-23.0%, 62.50+/-24.89%, 56.75+/-20.14%, PC:Ag: 5.31+/-1.63 microg/mL, 2.28+/-1.15 microg/mL, 2.43+/-0.79 microg/mL, P<0.05). The levels of PC:Ag in patients with acute viral hepatitis (AVH) also was lower (2.98+/-0.91 microg/mL, P<0.01), but PC:C was close to the control (93.76+/-30.49%, P>0.05). The levels of DCPC in patients with HCC were remarkably higher (0.69+/-0.29 microg/mL, 1.18+/-0.63 microg/mL, 0.45+/-0.21 microg/mL, P<0.05) and its average was up to 50% of total PC:Ag. But those of DCPC in patients with AVH were not significantly different from the control. The levels of total prothrombin were lower in patients with LC, but higher in patients with HCC. The levels of unabsorbed prothrombin were predominantly higher than those of other groups., Conclusion: PC:C and PC:Ag in patients with liver diseases (except PC:C in AVH) were lower. The total prothrombin was lower in patients with LC. The higher level of unabsorbed prothrombin may be used as a scanning marker for HCC. DCPC may be used as a complementary marker in the diagnosis of HCC.