PMID- 9736420
OWN - NLM
STAT- MEDLINE
DCOM- 19981117
LR  - 20220224
IS  - 0049-3848 (Print)
IS  - 0049-3848 (Linking)
VI  - 91
IP  - 4
DP  - 1998 Aug 15
TI  - Differential effects of low molecular weight heparin and unfractionated heparin 
      on circulating levels of antithrombin and tissue factor pathway inhibitor (TFPI): 
      a possible mechanism for difference in therapeutic efficacy.
PG  - 177-81
AB  - There is growing evidence on the superior efficacy and safety of low molecular 
      weight heparins (LMWHs) over unfractionated heparin (UFH) for the treatment of 
      both venous and arterial thromboembolism. Heparin exerts its function by 
      potentiating antithrombin and by mobilizing tissue factor pathway inhibitor 
      (TFPI) into the circulation. The present study was conducted to compare the 
      effect of subcutaneous LMWH and infusion of UFH on these two anticoagulants in 
      plasma. Eighteen healthy male volunteers were randomly allocated to therapy with 
      continuous intravenous (iv) UFH (n=6) (initial infusion rate 450 IU/kg/day) or 
      low molecular weight heparin (LMWH) (enoxaparin, 1.5 mg/kg/day) subcutaneously 
      (sc) once daily for 72 hours. Free TFPI antigen, measured by a solid-phase 
      two-site enzyme immunoassay, and antithrombin and protein C activities, measured 
      by chromogenic assays, were assessed in plasma samples before, during, and after 
      anticoagulant treatment. Infusion of UFH, but not subcutaneous LMWH, was found to 
      attenuate the antithrombotic defense by a selective decrease of both circulating 
      antithrombin (-21+/-7%, p<0.0001) and of free and endothelial-bound TFPI. The 
      changes in antithrombin and TFPI by LMWH and UFH were statistically different 
      between groups (p<0.001). The differential effect of UFH and LMWH on antithrombin 
      and TFPI may explain the superior efficacy of subcutaneous LMWH compared with 
      conventional intravenous UFH for treatment of both arterial and venous 
      thrombosis.
FAU - Hansen, J B
AU  - Hansen JB
AD  - Department of Medicine, Institute of Clinical Medicine, University of Tromso, 
      Norway. johnbh@fagmed.uit.no
FAU - Sandset, P M
AU  - Sandset PM
LA  - eng
PT  - Clinical Trial
PT  - Comparative Study
PT  - Journal Article
PT  - Randomized Controlled Trial
PL  - United States
TA  - Thromb Res
JT  - Thrombosis research
JID - 0326377
RN  - 0 (Anticoagulants)
RN  - 0 (Antithrombins)
RN  - 0 (Heparin, Low-Molecular-Weight)
RN  - 0 (Lipoproteins)
RN  - 0 (Protein C)
RN  - 0 (lipoprotein-associated coagulation inhibitor)
RN  - 9005-49-6 (Heparin)
SB  - IM
MH  - Administration, Cutaneous
MH  - Adult
MH  - Anticoagulants/*administration & dosage
MH  - Antithrombins/*metabolism
MH  - Heparin/*administration & dosage
MH  - Heparin, Low-Molecular-Weight/*administration & dosage
MH  - Humans
MH  - Infusions, Intravenous
MH  - Lipoproteins/*blood
MH  - Male
MH  - Protein C/metabolism
EDAT- 1998/09/15 00:00
MHDA- 1998/09/15 00:01
CRDT- 1998/09/15 00:00
PHST- 1998/09/15 00:00 [pubmed]
PHST- 1998/09/15 00:01 [medline]
PHST- 1998/09/15 00:00 [entrez]
AID - S0049-3848(98)00079-6 [pii]
AID - 10.1016/s0049-3848(98)00079-6 [doi]
PST - ppublish
SO  - Thromb Res. 1998 Aug 15;91(4):177-81. doi: 10.1016/s0049-3848(98)00079-6.