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Confluent cultures of endothelial cells from human umbilical cord were used to study the effect of activated human protein C (APC) on the production of plasminogen activators, plasminogen activator-inhibitor, and factor VIII-related antigen. Addition of APC to the cells in a serum-free medium did not affect the production of tissue-type plasminogen activator (t-PA) or factor VIII-related antigen; under all measured conditions, no urokinase activity was found. However, less plasminogen activator-inhibitor activity accumulated in the conditioned medium in the presence of APC. This decrease was dose dependent and could be prevented by specific anti-protein C antibodies. No decrease was observed with the zymogen protein C or with diisopropylfluorophosphate-inactivated APC. APC also decreased the t-PA inhibitor activity in endothelial cell-conditioned medium in the absence of cells, which suggests that the effect of APC is at least partly due to a direct effect of APC on the plasminogen activator-inhibitor. High concentrations of thrombin-but not of factor Xa or IXa--had a similar effect on the t-PA inhibitor activity. The effect of APC on the plasminogen activator-inhibitor provides a new mechanism by which APC may enhance fibrinolysis. The data suggest that activation of the coagulation system may lead to a secondary increase of the fibrinolytic activity by changing the balance between plasminogen activator(s) and its (their) fast-acting inhibitor.
V W van Hinsbergh, and
R M Bertina, and
A van Wijngaarden, and
N H van Tilburg, and
J J Emeis, and
F Haverkate
March 1993,
Thrombosis and haemostasis,
V W van Hinsbergh, and
R M Bertina, and
A van Wijngaarden, and
N H van Tilburg, and
J J Emeis, and
F Haverkate
November 1987,
Biochemistry,
V W van Hinsbergh, and
R M Bertina, and
A van Wijngaarden, and
N H van Tilburg, and
J J Emeis, and
F Haverkate
March 1998,
Human cell,
V W van Hinsbergh, and
R M Bertina, and
A van Wijngaarden, and
N H van Tilburg, and
J J Emeis, and
F Haverkate
November 1989,
Nihon Ketsueki Gakkai zasshi : journal of Japan Haematological Society,
V W van Hinsbergh, and
R M Bertina, and
A van Wijngaarden, and
N H van Tilburg, and
J J Emeis, and
F Haverkate
October 2005,
Arteriosclerosis, thrombosis, and vascular biology,
V W van Hinsbergh, and
R M Bertina, and
A van Wijngaarden, and
N H van Tilburg, and
J J Emeis, and
F Haverkate
January 2008,
Thrombosis research,
V W van Hinsbergh, and
R M Bertina, and
A van Wijngaarden, and
N H van Tilburg, and
J J Emeis, and
F Haverkate
January 1993,
Haemostasis,
V W van Hinsbergh, and
R M Bertina, and
A van Wijngaarden, and
N H van Tilburg, and
J J Emeis, and
F Haverkate
January 1996,
Polish journal of pharmacology,
V W van Hinsbergh, and
R M Bertina, and
A van Wijngaarden, and
N H van Tilburg, and
J J Emeis, and
F Haverkate
July 1989,
Biochemistry,
V W van Hinsbergh, and
R M Bertina, and
A van Wijngaarden, and
N H van Tilburg, and
J J Emeis, and
F Haverkate
June 1993,
Thrombosis research,
