[The regulation of blood coagulation and fibrinolysis by vascular endothelial cells].

Vascular endothelial cells play a critical role in the regulation of coagulation and fibrinolysis by controlling the expression of tissue factor (TF), tissue factor pathway inhibitor (TFPI), plasminogen activator inhibitor-1 (PAI-1), and tissue type plasminogen activator (TPA). Vasoconstrictors can induce TF and PAI-1 expression without changing the TFPI or TPA expression level. Vasodilators can not alter that of TFPI or TPA, but they inhibit the induction of TF or PAI-1 by vasoconstrictors. These results suggest that by making TF predominant to TFPI and PAI-1 to TPA, vasoconstrictors cause the vascular endothelial cells to become thrombogenic and vasodilators inhibit this process. The thrombogenicity by vasoconstrictors may be originally involved in the protective mechanisms against bleeding, and antithrombogenicity by vasodilators may be originally a part of the protective mechanisms against stasis. In treating hypertension, it is necessary to consider this thrombogenicity by vasoconstrictors in order to avoid iatrogenic thrombotic disease.