| Abstract: | The action of the hypolipaemic drug niceritrol (INN) on cholesterol accumulation in the aorta was studied in cholesterol-fed rabbits at three levels of plasma cholesterol, approximately 100, 500–1000 and 2000 mg/100 ml. This was achieved by feeding diets with three different concentrations of cholesterol. The two higher but not the lowest concentration resulted in a large increase in plasma cholesterol as well as in a moderate lipid infiltration of the aorta. On addition of 0.5–1% niceritrol to the diet there was a significant reduction of plasma cholesterol in all three series. In the series with the lowest plasma cholesterol level the degree of atherosclerotic changes were so slight that the effect of niceritrol could not be evaluated. In the series with plasma cholesterol up to 1000 mg/100 ml niceritrol markedly inhibited the lipid infiltration of the aorta. In the series with the highest plasma cholesterol level niceritrol had no protective effect. The relationship between plasma cholesterol levels and extent of aortic lipid infiltration was studied in a pooled reference material of 154 cholesterol-fed rabbits. The demonstrated type of relationship could largely explain the difference in the protective action of niceritrol in the three series. |
