Different pharmacokinetics, antithrombotic activity and bleeding effects of heparin and two new fragments administered in rat by subcutaneous route.

Native heparin (CAS 9005-49-6) and its two new fragments, low molecular weight heparin (LMW-H, 5 kDa) and oligo-heparin (oligo-H, 2 KDa) obtained by radical degradation were characterized as to their physicochemlecular weight. LMW-H and oligo-H exhibit greater antithrombotic activity than unfractionated heparin when administered subcutaneously. The pharmacokinetic behaviour off oligo-H considerably differs from that off unfractionated heparin and LMW-H. This new drug is able to bind cells and plasma proteins differently from heparin and LMW-H