Circulating Osteocalcin During Oral Anticoagulant Therapy

Summary

In this paper we present the following observations:

1) In sheep vitamin K-antagonists like phenprocoumon induce a decrease of the serum levels of osteocalcin (bone Gla-protein) and of the affinity of the circulating osteocalcin for hydroxyapatite.

2) In sheep vitamin K counteracts the effect of phen-procoumon on the blood coagulation system, but not that on the osteocalcin production.

3) In human subjects vitamin K-antagonists also lead to decreased levels of serum osteocalcin and a low affinity of the protein for hydroxyapatite.

4) These two variables reached steady-state levels within 24 h after the start of oral anticoagulant treatment and - at continu-ation of the therapy - they remained low for at least several years.

Key words

Osteocalcin - Vitamin K - Oral anticoagulants - Gammacar - boxyglutamic acid - Blood coagulation - Bone

• References

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