This article summarizes the series of experiments done in New Zealand rabbits that developed aortic lesions being fed a high cholesterol diet, varying from 0,5% to 1,5% of the chow. Planimetry in statin treated rabbits showed a reduction of the lesions. Interpreted mainly by its antioxidant properties the probucol drug presented the bigger reduction of the aortic atherosclerotic lesions. The lesions could be proven to be richer in Calcium by a specific coloring technique, von Kossa. This was found in the deep layer of the intima. Fibrates as well were tested and the main observation was the reduction in fibrinogen concentration in this particular experimental model. These findings raised hypothesis leading to the action of antithrombotic drugs. Aiming at the observation of antithrombotic action another group was submitted to aspirin treatment. Although it did not have any effect on the extension of the aortic atherosclerotic lesions, a reduction in the blood aggregation was significant. This effect was interpreted as a probable protection factor in case of ruptured plaques, diminishing the chance of thrombus formation and aortic occlusion in this hypercholesterolemia rabbits.