Abstract Numerous systemic infections may have hypercoagulation as one of the complications, which range from asymptomatic presentation elevation biochemical markers coagulation such that fibrin and thrombin generation, to a much severe, symptomatic, life-threatening, disseminated intravascular (DIC), results in formation thrombi microvasculature various organs. This phenomenon contributes incr...

Endothelial cells express negligible amounts of tissue factor (TF) that can be induced by thrombin, which is important for acute coronary syndromes. Recent research suggests that endothelial TF expression is positively regulated by RhoA and p38mapk, but negatively by Akt/endothelial nitric oxide synthase (eNOS) pathway. High-density lipoprotein (HDL) is atheroprotective and exerts antiatherothr...

In the present study, we differentiated between short- and long-term effects of vasoactive compounds on human endothelial permeability in an in vitro model. Histamine induced a rapid and transient (<3 minutes) decrease in barrier function, as evidenced by a decreased transendothelial electrical resistance and an increased passage of 22Na ions. This increase in permeability was inhibited complet...

Thrombin is a multifunctional serine protease, which is involved in blood coagulation and thrombosis, inflammation and wound repair in tissue injury. Its role in the amelioration of inflammatory tissue injury has been investigated. Protease-activated cell surface receptors (PARs) when activated by thrombin result in the production of proinflammatory mediators. In the kidney, these PARs are expr...

The chemical modification of lysine residues in human alpha-thrombin has been used to study the interaction of thrombin with human platelets. Phosphopyridoxylation of thrombin using pyridoxal 5'-phosphate (pyridoxal-P) has been shown to inhibit the fibrinogen clotting activity of thrombin but not the catalytic activity (Griffith, M. J. J. Biol. Chem. 254, 3401-3406). Phosphopyridoxylation resul...

The active site tripeptide arginal inhibitor of thrombin, LY287045, was used to study thrombin-induced aortic relaxation and contraction, two responses that differ both pharmacologically and physiologically. Although thrombin (10(-7) M) and trypsin (10(-6) M) were tachyphylactic upon repeated administration, trypsin contracted the aorta following thrombin-induced contraction. LY287045 (10(-7) M...

Thrombin is a key serine protease involved in the blood cascade. Two small molecular inhibitors, 4-nitrophenyl diethylphosphate (paraoxon) and 4-nitrophenyl 2-propyl methylphosphonate (MPNP), covalently bond to the active-site Ser to form a mimic of the tetrahedral intermediate found in thrombin-catalyzed reactions. The pH dependence of their inhibition of human α-thrombin at 25.0 + 0.1C was de...

Heparan sulphate and dermatan sulphate have both antithrombotic and anticoagulant properties. These are, however, significantly weaker than those of a comparable amount of standard pig mucosal heparin. Antithrombotic and anticoagulant effects of glycosaminoglycans depend on their ability to catalyse the inhibition of thrombin and/or to inhibit the activation of prothrombin. Since heparan sulpha...

The effects of endothelin-1 (ET-1) on P-selectin-mediated leukocyte endothelial interaction were examined in vitro. Adherence of autologous polymorphonuclear leukocytes (PMNs) to the endothelium was markedly enhanced by endothelial stimulation with either (2 U/mL) thrombin, (1 mumol/L) histamine, or (100 nmol/L) phorbol myristate acetate (PMA). In contrast, ET-1 alone (10 and 100 nmol/L) only s...