CLINICAL ENCOUNTERS
ANTICOAGULATION
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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It will remove Ca2+ through chelation.
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It will forms a complex with antithrombin III, catalyzing the inhibition of thrombin.
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It will removes calcium from coagulation system by precipitating it into unusable form.
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It will add calcium ion in blood preventing clotting.
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Detailed explanation-1: -Heparins bind to antithrombin (AT) and induce a conformational change that makes AT an efficient inactivator of coagulation factors. Unfractionated heparin inhibits thrombin (factor IIa) by forming a ternary complex.
Detailed explanation-2: -The mechanism of action of heparin is ATIII-dependent. It acts mainly by accelerating the rate of the neutralization of certain activated coagulation factors by antithrombin, but other mechanisms may also be involved. The antithrombotic effect of heparin is well correlated to the inhibition of factor Xa.
Detailed explanation-3: -Mechanism of action Antithrombin III inhibits clotting factors IIa (thrombin), Xa, and to a lesser extent IXa and XIIa. UFH and LMWH bind to antithrombin III via a pentasaccharide group, inducing a conformational change which enhances antithrombin-mediated inhibition of these clotting factors.
Detailed explanation-4: -Unfractionated heparin enhances the rates at which antithrombin III inactivates activated clotting factors, and inhibits the activation of both Factor X and prothrombin by disrupting the calcium and phospholipid dependent assembly of the Factor X and prothrombin activator complexes.