COMPARATIVE STUDIES ON THE PREVENTIVE EFFECT OF PYRIDINOLCARBAMATE AND ESTROGEN AGAINST AORTIC AND CORONARY ATHEROSCLEROSIS OF CHOLESTEROL-FED RABBITS

The antiatherosclerotic effects of pyridinolcarbamate and estrogen, both of which have a preventative effect against acute edematous vascular injury, were studied using 40 rabbits. Ten rabbits each received orally 0.1 mg/kg or 1 mg/kg of diethylstilbestrol, 10 mg/kg of pyridinolcarbamate or potato starch as a placebo. All were fed cholesterol for 15 weeks. Treatment with pyridinolcarbamate of 1 mg/kg of diethylstilbestrol was shown to exert a powerful effect in preventing the appearance of atheromatous changes (p<0.01) but 0.1 mg/kg of diethylstilbestrol did not show a preventative effect. The three treated groups exhibited protection against coronary atherosclerosis which was statistically significant when compared with the controls. Atheromas in rabbits treated with pyridinolcarbamate were characterized his-tologically by the regeneration of smooth muscle fibers and those treated with diethylstilbestrol by fibrous healing. Necrotic foci or calcification was sometimes encountered, especially in the rabbits treated with 1 mg/kg of diethylstilbestrol. These preventative properties of the substances studied are possibly much related to inhibit permeability-enhancing conditions of the arterial wall.