Antithrombotic effect of a mucopolysaccharide polysulfate after systemic, topical and percutaneous application

Antithrombotic activity of mucopolysaccharide polysulfuric acid ester (MPS) was investigated in vitro as well as in animal models of thrombosis. In vitro studies were performed by using native human blood and the haemostatometer. MPS (greater than or equal to 25 micrograms/ml) caused concentration dependent inhibition of the in vitro haemostasis (platelet reactivity). Antihaemostatic activity of epoprostenol (prostacyclin) was synergized by MPS. In vivo platelet thrombus formation was induced by laser irradiation in the microvasculature of hamster cheek pouch. The time until occlusion of the irradiated small vein and the duration of occlusion were measured. MPS administered intravenously at a dose range of 1-10 mg/kg b.w. inhibited thrombus formation and prolonged the time until occlusion of the irradiated vessel. Upon topical administration of a solution of 1, 5 or 25% MPS the occlusion time was also prolonged. Topical application of MPS as a 0.3% cream (Hirudoid) increased the occlusion time significantly. 24 h percutaneous application of 0.3% MPS cream but not the placebo on the back skin of rats resulted in a significant (p less than 0.001) inhibition of thrombus formation in the microvessels of the mesoappendix. A common finding at all modes of administration of MPS was that reperfusion of the occluded vessel occurred much earlier in MPS treated animals than in the controls.