Behavior of protein S during long-term oral anticoagulant therapy

Thromb Res. 1988 Aug 1;51(3):241-9. doi: 10.1016/0049-3848(88)90101-6.

Abstract

It has recently been reported that a natural anticoagulant, protein S (PS), is depressed during oral anticoagulation. Since more detailed information is required from the clinical standpoint, we measured plasma levels of PS [both total and free (not complexed) PS antigen], C4b-binding protein (C4bp) and other vitamin K-dependent proteins (factors II, VII, IX, X and protein C) in 60 plasma samples from patients on long-term oral anticoagulant therapy with warfarin. Together with the reduction of other vitamin K-dependent plasma proteins, PS decreased during warfarin treatment, being dependent on the intensity of the therapy. A considerable variation in plasma PS levels was also observed among individuals with a similar intensity of anticoagulation. Plasma concentration of C4bp was closely correlated with total PS level, and free PS/total PS ratio was independent of thrombotest values. These findings indicate that long-term oral anticoagulant therapy results in the suppression of the synthesis of PS, and that its reduction is on the whole balanced with C4bp and vitamin K-dependent coagulation factors. It was suggested that the metabolism of C4bp might be regulated by the plasma PS level, although this hypothesis needs further exploration.

MeSH terms

  • Administration, Oral
  • Blood Proteins / analysis
  • Glycoproteins / blood*
  • Humans
  • Protein S
  • Time Factors
  • Warfarin / administration & dosage
  • Warfarin / pharmacology*

Substances

  • Blood Proteins
  • Glycoproteins
  • Protein S
  • Warfarin