The drug heparin acts in hemostasis by which processes?
A)Inhibiting thrombin and antithrombin III (AT-III)
B)Preventing the conversion of prothrombin to thrombin
C)Shortening the fibrin strands to retract the blood clot
D)Degrading the fibrin within blood clots

Question

Quizplus · Accepted Answer

Clinically administered heparin binds to AT-III and induces a conformational change that greatly enhances its activity. Under normal conditions, the presence of endothelial cell heparin sulfate and available AT-III in the circulation cooperate to protect the vessels from the effects of spontaneously activated thrombin. Heparin does not prevent the conversion of prothrombin to thrombin, shorten fibrin strands, or degrade the fibrin in blood clots.

The Drug Heparin Acts in Hemostasis by Which Processes