title: [Effects of tetramethylpyrazine on thrombin-induced tissue factor expression in vascular endothelial cells].
abstract: 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).
  
  
  CONCLUSIONS
  Thrombin induces TF expression in vascular endothelial cells, and this effect can be inhibited by TMP at the mRNA level.
authors.affiliation: Xiangya Medical School, Central South University, Changsha 410078, China. ccy540401@126.com
authors.forename: Chun-ying
authors.initials: CY
authors.lastname: Cheng
authors.forename: Yong
authors.initials: Y
authors.lastname: Sun
authors.forename: Zhi-bin
authors.initials: ZB
authors.lastname: Wen
authors.forename: Xiao-fan
authors.initials: XF
authors.lastname: He
authors.forename: Gu-feng
authors.initials: GF
authors.lastname: Wang
authors.forename: Guo-qiang
authors.initials: GQ
authors.lastname: Lin
authors.forename: Hai-he
authors.initials: HH
authors.lastname: Jiang
authors.forename: Xian-ming
authors.initials: XM
authors.lastname: Tian
authors.forename: Shi-lin
authors.initials: SL
authors.lastname: He
mesh_terms: D000818:Animals; D002460:Cell Line; D004305:Dose-Response Relationship, Drug; D042783:Endothelial Cells / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism*; D005786:Gene Expression Regulation / Q000187:drug effects*; D006801:Humans; D011719:Pyrazines / Q000494:pharmacology*; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D013917:Thrombin / Q000494:pharmacology*; D013925:Thromboplastin / Q000235:genetics* / Q000378:metabolism; D013997:Time Factors
chemical_list: D011719:Pyrazines; D012333:RNA, Messenger; D013925:Thromboplastin; D013917:Thrombin; C017953:tetramethylpyrazine