INTERACTION OF A NEW DEPOLYMERIZED HOLOTHURIAN GLYCOSAMINOGLYCAN WITHPROTEINS IN HUMAN PLASMA

In a rat template bleeding model, depolymerized holothurian glycosamin oglycan (DHG) prolonged bleeding time at 30 mg/kg i.v. but unfractiona ted heparin (UFH) had the same effect at 1 mg/kg i.v., indicating that DHG is much less bleeding than UFH. To characterize this difference, we examined the affinity of DHG for plasma proteins by means of a glyc osaminoglycan-conjugated cellulofine column in comparison with that of UFH. The DHG column strongly bound factor V, factor IX, protein S, hi stidine-rich glycoprotein, platelet factor 4 (PF4), beta -thromboglobu lin, von Willebrand factor, fibronectin, and heparin cofactor II, but did not bind fibrinogen, prothrombin, factor VII, protein C, antithrom bin III (ATIII), plasminogen or alpha 2-plasmin inhibitor. The profile of protein binding to the UFH column was almost the same as that of t he DHG column except that ATIII showed affinity for UFH. One of the re asons why DHG caused much less bleeding than UFH is thus suggested to be the differences in their affinity for ATIII in plasma.