Abstract
Highly active heparan sulfate was isolated from bovine kidney by affinity chromatography on antithrombin III-Sepharose.
High-affinity heparan sulfate (A-HS) accounted for only about 1% of the total HS. There were no significant differences between A-HS and nonaffinity heparan sulfate (NA-HS) in mobility by electrophoresis, in susceptibility to heparitinase and in chemical properties.
The anticoagulant activity of A-HS was 64units/mg by APTT method heparin as the standard, while NA-HS showed only 1unit/mg. In the assay, high-affinity heparin (A-Hep), prepared by antithrombin III-Sepharose affinity chromatography, had 4.5-fold higher specific activity than A-HS.
A-HS preferentially potentiated the inhibitory activity of antithrombin III for factor Xa rather than for factor IIa. On the other hand, the reversed results were obtained for A-Hep. A-HS showed its highest specific activity in potentiation of antithrombin III at the molecular weight of 13, 500.
Anti-Xa activity of A-HS measured by prothrombin/thrombin conversion assay was 3.8-fold lower than anticoagulant activities described above.
These results suggest that A-HS might contain an antithrombin III binding region smilar to that of A-Hep in the molecule despite the differences in the chemical properties of the two glycosaminoglycans.
