[Duodenal absorption of a low molecular weight heparin in rabbits].

Commercial heparin cannot practically cross the intestinal barrier. Meanwhile, because of the theoretical interest in oral heparin therapeutics, we applied our studies to a low molecular weight heparin fraction (3 000 to 4 000 D). This fraction was directly injected into anaesthetized rabbit duodenum. For an equal anticoagulant activity (expressed in international units), commercial heparin is not absorbed whereas the low molecular weight fraction mainly induces an early plasmatic anti-Xa activity which remains over the fifth hour.