PMID- 7900078
OWN - NLM
STAT- MEDLINE
DCOM- 19950426
LR  - 20220321
IS  - 0340-6245 (Print)
IS  - 0340-6245 (Linking)
VI  - 72
IP  - 5
DP  - 1994 Nov
TI  - The effect of subcutaneous injection of unfractionated and low molecular weight 
      heparin on thrombin generation in platelet rich plasma--a study in human 
      volunteers.
PG  - 705-12
AB  - We administered a dose of unfractionated heparin (UFH) and two doses of a low 
      molecular weight heparin (LMWH) to healthy volunteers by SC injection. The doses 
      given were: a) UFH, 5000 IU, which represents 8.7 mg of > 5,400 MW active heparin 
      (ACLM) and no < 5,400 active heparin (BCLM), b) enoxaparin 40 mg (3.4 mg ACLM, 
      2.2 mg BCLM) and c) enoxaparin 1 mg/kg body weight (on the mean 75 mg, containing 
      6.4 mg ACLM and 4.1 mg BCLM). We determined the effect on thrombin generation in 
      platelet rich plasma (PRP) between 1 and 8 h after injection. UFH administration 
      caused only a 5-8% inhibition of the thrombin potential (i.e. the area under the 
      thrombin generation curve). Significantly higher inhibition of the thrombin 
      potential was seen after administration of both doses of enoxaparin. To wit 9-26% 
      at the low dose and 29-46% at the high dose. UFH injection caused a prolongation 
      of the lag-time before the thrombin burst. Only with the high dose of enoxaparin 
      the lag-times were significantly more prolonged with enoxaparin than with UFH. 
      Excess amounts of platelet factor 4 (PF4) were able to neutralize completely the 
      anti-thrombin activity in normal plasma spiked with enoxaparin as well as in 
      plasma samples obtained after SC enoxaparin injection. With a large excess of PF4 
      the anti-factor Xa activity could be inhibited to a maximum of 50%. This 
      indicates that ACLM (above critical length material, MW > 5400) is neutralized 
      completely by PF4 whereas BCLM (below critical length material, MW < 5400) is 
      not.(ABSTRACT TRUNCATED AT 250 WORDS)
FAU - Bendetowicz, A V
AU  - Bendetowicz AV
AD  - Department of Biochemistry, Cardiovascular Research Institute Maastricht, The 
      Netherlands.
FAU - Kai, H
AU  - Kai H
FAU - Knebel, R
AU  - Knebel R
FAU - Caplain, H
AU  - Caplain H
FAU - Hemker, H C
AU  - Hemker HC
FAU - Lindhout, T
AU  - Lindhout T
FAU - Beguin, S
AU  - Beguin S
LA  - eng
PT  - Clinical Trial
PT  - Controlled Clinical Trial
PT  - Journal Article
PL  - Germany
TA  - Thromb Haemost
JT  - Thrombosis and haemostasis
JID - 7608063
RN  - 0 (Heparin Antagonists)
RN  - 0 (Heparin, Low-Molecular-Weight)
RN  - 37270-94-3 (Platelet Factor 4)
RN  - 9005-49-6 (Heparin)
RN  - EC 3.4.21.5 (Thrombin)
SB  - IM
MH  - Adult
MH  - Heparin/*pharmacology
MH  - Heparin Antagonists/pharmacology
MH  - Heparin, Low-Molecular-Weight/antagonists & inhibitors/*pharmacology
MH  - Humans
MH  - Injections, Subcutaneous
MH  - Kinetics
MH  - Male
MH  - Platelet Count
MH  - Platelet Factor 4/pharmacology
MH  - Reaction Time
MH  - Reference Values
MH  - Thrombin/*biosynthesis
EDAT- 1994/11/01 00:00
MHDA- 1994/11/01 00:01
CRDT- 1994/11/01 00:00
PHST- 1994/11/01 00:00 [pubmed]
PHST- 1994/11/01 00:01 [medline]
PHST- 1994/11/01 00:00 [entrez]
PST - ppublish
SO  - Thromb Haemost. 1994 Nov;72(5):705-12.