High and low affinity heparin compared with unfractionated heparin as antithrombotic drugs
Merton, R.E.; Thomas, D.P.; Havercroft, S.J.; Barrowcliffe, T.W.; Lindahl, U.
Thrombosis and Haemostasis 51(2): 254-256
1984
ISSN/ISBN: 0340-6245 PMID: 6740557 Document Number: 232224
A preparation of heparin was separated by affinity chromatography into two fractions: one of high ( HAH ) and the other of low (LAH) affinity to antithrombin III. These two fractions were compared with unfractionated heparin ( UFH ) by in vitro assay and their ability to impair experimental stasis thrombosis was also examined. Although the in vitro activity of HAH was double that of UFH , HAH was less effective than UFH as an antithrombotic drug; LAH was virtually inactive, both in vitro and in vivo. A mixture of 30 micrograms/kg of HAH and 50 micrograms/kg of LAH was as effective in preventing thrombosis as 80 micrograms/kg of UFH , and was more effective than 40 micrograms/kg of HAH alone, demonstrating that LAH potentiates the action of HAH in vivo.