Thromb Haemost 1988; 59(02): 147-150
DOI: 10.1055/s-0038-1642744
Original Article
Schattauer GmbH Stuttgart

The In Vivo Effects of Oral Anticoagulants in Man: Comparison Between Liver and Non-Hepatic Tissues

Marian de Boer-van den Berg
*   The Department of Biochemistry, University of Limburg, Maastricht, The Netherlands
,
Henk H W Thijssen
**   The Department of Pharmacology, University of Limburg, Maastricht, The Netherlands
,
Cees Vermeer
*   The Department of Biochemistry, University of Limburg, Maastricht, The Netherlands
› Author Affiliations
Further Information

Publication History

Received 25 June 1987

Accepted after revision 29 October 1987

Publication Date:
21 May 2018 (online)

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Summary

The in vivo effects of oral anticoagulant therapy with 4–hydroxycoumarins on various vitamin K–dependent enzyme systems in man were compared. In hepatic microsomes obtained from donors who has been treated with 4–hydroxycoumarins for more than 6 months, the vitamin K 2,3 epoxide reductase activity and the DTT–dependent vitamin K quinone reductase activity were diminished to 35% and 20% of the corresponding normal values. In the non–hepatic tissues, only a small decrease in vitamin K 2,3 epoxide reductase activity could be demonstrated, while no differences were found in the vitamin K quinone reductase activities. In none of the tissues a significant increase of non–carboxylated precursor proteins was observed, whereas also vitamin K hydroquinone–dependent carboxylase activities seemed to be unaffected by the anticoagulant treatment.