An Antithrombin-Heparin Complex Increases <?layout cmd="newline"?> the Anticoagulant Activity of Fibrin Clots : Figure 3

]>An Antithrombin-Heparin Complex Increases <?layout cmd="newline"?> the Anticoagulant Activity of Fibrin Clots : Figure 3

(a)

(b)

Figure 3: Model of catalysis of thrombin inhibition by fibrin-bound antithrombin-heparin covalent complex (ATH). The fibrin (blue) clot-bound thrombin-ATH (thrombin in yellow, antithrombin (AT) in green, heparin in red) is able to catalyze thrombin inhibition by AT since the heparin chain is available to bind both free thrombin and AT (panel (a)). In the case of noncovalently linked heparin, the heparin-catalyzed inhibition of thrombin by AT is negated through the formation of a fibrin-thrombin-heparin ternary complex (panel (b)).