antithrombin(redirected from Antithrombins)
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any naturally occurring or therapeutically administered substance that neutralizes the action of thrombin and thus limits or restricts blood coagulation.
antithrombin I fibrin, referring to the capacity of fibrin to adsorb thrombin and thus neutralize it.
antithrombin III a naturally occurring inhibitor of blood coagulation; it is an α2-globulin member of the serpin group, synthesized in the liver and found in the plasma and various extravascular sites. It inactivates thrombin as well as certain coagulation factors and kallikrein. Inherited deficiency of the protein, an autosomal dominant disorder, is associated with recurrent deep vein thrombosis and pulmonary emboli. Complications from the disorder are prevented and, in conjunction with heparin, treated with a preparation of antithrombin III from pooled human plasma, administered intravenously.
Any substance that inhibits or prevents the effects of thrombin in such a manner that blood does not coagulate. A deficiency of antithrombin results in impaired inhibition of coagulation factors IIa, IXa, and Xa in plasma, causing recurrent thrombosis.
antithrombinA plasma protein that diminishes the activity of THROMBIN, or the amount of thrombin produced during or following coagulation of the blood.
Any substance that counters the effect of thrombin, an enzyme that converts fibrinogen into fibrin, leading to blood coagulation.
Mentioned in: Hypercoagulation Disorders