Jean Millet

Effect of low‐molecular‐weight fucoidan on experimental arterial thrombosis in the rabbit and rat

was used to perform an extra-corporeal arteriovenous shunt between the carotid artery and the jugular vein ; mean times for formation of an occlusive thrombus in the carotid artery were determined in control and treated animals. Both fucoidan and unfractionated heparin, injected intravenously 5 min before thrombosis induction, inhibited thrombus formation significantly. LMW fucoidan and heparin increased mean time-to-occlusion about three-fold in the same concentration range (2 mg/kg fucoidan 43.7 + 5.5 min and 1 mg/kg heparin 55.4 + 2.6 versus control 15.6 + 1.6 min ; 5 animals per group ; p < 0.001). The anti-thrombotic effect of fucoidan was also evaluated in this model after subcutaneous injection 2 h before thrombosis induction. With a dose of 7.5 mg/kg, time-to-occlusion was prolonged significantly (22.8 + 3.4 min in the treated group

Experimental venous thrombosis induced by homologous serum in the rat

To investigate the effects of new drugs on the prevention of venous thrombosis, the Wessler stasis model is extensively employed usually in the rabbit. In this model, a hypercoagulable state is achieved by the administration of either heterologous serum (often human serum) or an activated coagulation factor followed by total stasis of the vein in which the thrombus is to be formed. Although classically the stasis model is performed in rabbits, it is possible to induce experimental venous thrombosis in a number of animal species, including rats. However, the use of homologous serum as the activating or thrombogenic agent has been previously described only in the dog and in the rabbit. The purpose of the present study was to compare the activities of heterologous and homologous serum as hypercoagulating agents in a rat stasis model of venous thrombosis using Wesslers technique. Heparin was employed as a reference antithrombotic compound in order to compare the two thrombogenic challenges.