Pharmacokinetics and organ distribution in rats of a low molecular weight heparin.

Fluorescein-labelled low molecular weight heparin (OP/LMWH) pharmacokinetics and organ distribution were studied in the rat after intravenous administration at doses of 3 and 15 mg/kg. The pharmacokinetics of labelled OP/LMWH was dose-dependent like heparin, however, the anticoagulant activity such as anti-Xa was more prolonged. The rapidity of the disappearance of the fluorescence was quicker than the biological activity.

Antithrombotic effect of OP/LMWH by subcutaneous route in rats.

The aim of this study was to compare the antithrombotic and haemorrhagic effects of unfractionated heparin and OP/LMWH, a new low molecular weight heparin fragment, after subcutaneous administration in rats. Both heparins showed antithrombotic efficacy in a model of acute venous thrombosis even at 1 mg/kg; furthermore OP/LMWH presented a significantly higher activity in subacute venous thrombosis of the rat. At all the dosages tested OP/LMWH showed a significantly shorter bleeding time in the rat by the "transection" method, compared with unfractionated heparin.

Studies of chemical and biologic properties of a fraction of sulodexide, a heparin-like glycosaminoglycan.

The chemical composition and biologic properties of a fraction (f) of Sulodexide, a heparin-like GAG, were studied and compared with those of two sulfated GAG preparations and heparin from intestinal mucosa. f-Sulodexide and the sulfated GAG preparations were fractionated on a Dowex-1Cl- column and subsequently on an antithrombin III affinity column. Low affinity and high affinity fractions had similar chemical composition and lipoprotein lipase releasing ability, but they varied in anticoagulant activity.

Interaction of a new low molecular weight heparin (OP/LMWH) with human platelets.

In vitro platelet proaggregating effect of unfractionated heparin (H) and OP/LMWH were studied with human platelets. OP/LMWH produced a significant less potentiation of ADP and PAF induced aggregation and slightly counteracted the antiaggregating effect of PGI2, in comparison with H. The proaggregating effect of both heparins was neutralized by equal contemporaneous amount of protamine sulfate.