Effect of sulphated polysaccharides on the alpha 1-antitrypsin inhibition of amidolysis catalysed by coagulation cascade proteinases.

1 The ability of several sulphated polysaccharide anticoagulants to prevent alpha 1-antitrypsin inhibition of thrombin paralleled their ability to potentiate antithrombin III inhibition of thrombin. None of the compounds examined altered the ability of alpha 1-antitrypsin to inhibit activated coagulation factor X (Xa). 2 These results are consistent with the possibility that a direct polysaccharide-proteinase interaction may be involved in the sulphated polysaccharide-modulated inhibition of thrombin by antithrombin III.