Mechanism of potentiation of antithrombin III [AT-III] inhibition by sulfated xylans

Thromb Res. 1987 Aug 1;47(3):341-52. doi: 10.1016/0049-3848(87)90148-4.


Anticoagulant properties of three sulfated compounds prepared from xylans isolated from corn cobs, larchwood and oatspelts were compared with heparin and sodium pentosan polysulfate (SP-54) by studying their effects on activated partial thromboplastin time (APTT), prothrombin time (PT) and thrombin time (TT) using pooled normal human plasma. These compounds were more effective than SP-54 in delaying coagulation by all the three procedures while oatspelts xylan sulfate was as effective as heparin in inhibiting APTT and PT and more effective than heparin in inhibiting TT on a molar basis. The sulfated xylans were more effective than heparin or SP-54 in potentiating the AT-III inhibition of amidolysis of H-D-Phe-Pip-Arg-pNa (S-2238) by thrombin (IIa) or amidolysis of Bz-Ile-Glu-Gly-Arg-pNa (S-2222) by Xa. Study of the high affinity binding of the xylan sulfates to AT-III-Sepharose column showed that the amount of the xylan sulfate recovered in the eluates from this peak was greatly increased with an increase in molecular weight (MW). A buffered mixture of IIa, AT-III and dansylarginine N-(3-ethyl-1,5-pentanediyl) amide (DAPA) was used to study the inactivation of IIa by AT-III. Larchwood xylan sulfate (2-10 micrograms) was found to accelerate this inactivation which was neutralized by human platelet factor 4 (PF4). The results also suggested an interaction between larchwood xylan sulfate and IIa which may potentiate an interaction between AT-III and IIa.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Anticoagulants*
  • Antithrombin III / pharmacology*
  • Blood Coagulation Tests
  • Drug Synergism
  • Edible Grain / analysis
  • Factor X / antagonists & inhibitors
  • Factor Xa
  • Heparin / pharmacology
  • Humans
  • Molecular Weight
  • Pentosan Sulfuric Polyester / pharmacology
  • Polysaccharides / pharmacology*
  • Prothrombin / antagonists & inhibitors
  • Sulfates / pharmacology
  • Wood
  • Xylans / isolation & purification
  • Xylans / pharmacology*
  • Zea mays / analysis


  • Anticoagulants
  • Polysaccharides
  • Sulfates
  • Xylans
  • Pentosan Sulfuric Polyester
  • Antithrombin III
  • Prothrombin
  • Factor X
  • Factor IIa
  • Heparin
  • Factor Xa