PMID- 12855480
OWN - NLM
STAT- MEDLINE
DCOM- 20040204
LR  - 20061115
IS  - 1524-4636 (Electronic)
IS  - 1079-5642 (Linking)
VI  - 23
IP  - 9
DP  - 2003 Sep 1
TI  - Platelet activation induces cell-surface immunoreactive tissue factor expression, 
      which is modulated differently by antiplatelet drugs.
PG  - 1690-6
AB  - OBJECTIVE: Tissue factor (TF) is the main activator of the coagulation cascade 
      occurring in physiologic and pathologic conditions. Recent data suggest that 
      human platelets might contain TF that is possibly derived from leukocytes. In 
      this study, we investigated whether intraplatelet TF can be exposed on the 
      membrane by platelet agonists. The modulation of this process by antiplatelet 
      drugs has been evaluated as well. METHODS AND RESULTS: Flow cytometric analysis 
      of unstimulated platelets showed a small amount of membrane-associated 
      immunoreactive TF (irTF) in whole blood, platelet-rich plasma, and washed 
      platelets isolated from healthy subjects. ADP, thrombin receptor-activating 
      peptide, and epinephrine significantly increased functionally active, 
      membrane-associated irTF. ADP induced irTF exposure in a concentration- and 
      time-dependent fashion. Agonist-induced irTF expression was completely inhibited 
      by iloprost but not by aspirin. Interestingly, glycoprotein IIb/IIIa antagonists 
      did not inhibit but rather potentiated the stimulatory effect of ADP on platelet 
      irTF expression. Real-time polymerase chain reaction experiments showed 
      detectable amounts of TF mRNA in unstimulated platelets. CONCLUSIONS: These 
      findings indicate that platelet agonists and antiplatelet drugs might modulate 
      platelet-associated irTF expression. Regulated TF expression establishes the 
      potential for a previously unrecognized role for platelets in sustaining thrombus 
      formation and growth via coagulation-mediated mechanisms.
FAU - Camera, Marina
AU  - Camera M
AD  - Department of Pharmacological Sciences, University of Milan, Italy.
FAU - Frigerio, Marta
AU  - Frigerio M
FAU - Toschi, Vincenzo
AU  - Toschi V
FAU - Brambilla, Marta
AU  - Brambilla M
FAU - Rossi, Francesca
AU  - Rossi F
FAU - Cottell, David C
AU  - Cottell DC
FAU - Maderna, Paola
AU  - Maderna P
FAU - Parolari, Alessandro
AU  - Parolari A
FAU - Bonzi, Roberto
AU  - Bonzi R
FAU - De Vincenti, Ombretta
AU  - De Vincenti O
FAU - Tremoli, Elena
AU  - Tremoli E
LA  - eng
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
DEP - 20030710
PL  - United States
TA  - Arterioscler Thromb Vasc Biol
JT  - Arteriosclerosis, thrombosis, and vascular biology
JID - 9505803
RN  - 0 (Antigens, Surface)
RN  - 0 (Platelet Aggregation Inhibitors)
RN  - 0 (RNA, Messenger)
RN  - 9035-58-9 (Thromboplastin)
SB  - IM
MH  - Antigens, Surface/*biosynthesis/immunology/*metabolism/physiology
MH  - Blood Platelets/chemistry/drug effects/ultrastructure
MH  - Humans
MH  - Microscopy, Electron/methods
MH  - Platelet Activation/*drug effects/*physiology
MH  - Platelet Aggregation Inhibitors/*pharmacology
MH  - RNA, Messenger/metabolism
MH  - Thromboplastin/*biosynthesis/immunology/*metabolism/physiology
EDAT- 2003/07/12 05:00
MHDA- 2004/02/05 05:00
CRDT- 2003/07/12 05:00
PHST- 2003/07/12 05:00 [pubmed]
PHST- 2004/02/05 05:00 [medline]
PHST- 2003/07/12 05:00 [entrez]
AID - 01.ATV.0000085629.23209.AA [pii]
AID - 10.1161/01.ATV.0000085629.23209.AA [doi]
PST - ppublish
SO  - Arterioscler Thromb Vasc Biol. 2003 Sep 1;23(9):1690-6. doi: 
      10.1161/01.ATV.0000085629.23209.AA. Epub 2003 Jul 10.