Effects of ultra-low-dose aspirin on embolization in a model of laser-induced thrombus formation

A laser-induced rat mesenteric vessel thrombosis model was used to evaluate the effect of acetylsalicylic acid (ASA) at ultra-low doses. A partial occlusion was induced in small mesenteric vessels (diameter 40-50 mu m) by an argon laser. The laser induced damage of endothelial cells, Thrombi formed within seconds after the laser lesion and grew rapidly. Embolization began during the minute following the laser injury, Compared to placebo, the administration of ASA at ultra-low doses (334 x 10(-11) mol/mL) by subcutaneous injection in the thorax region (0.2 mL) induced three different phenomena: (1) a decrease in the number of laser injuries required to induce thrombus formation, (2) an increase in number of emboli removed by the blood stream, and (3) an increase in the duration of embolization, The ultra-low doses of ASA showed a strong increase in the number of emboli and in the duration of embolization.