Effect of addition of 10% Amberlite XAD-2 to the diet on serum cholesterol and atherogenesis in rabbits.

The effects of addition of the polystyrene resin XAD-2 to the diet of rabbits on serum cholesterol, on hepatic enzyme of cholesterol synthesis (HMG-CoA reductase), and on atherogenesis was determined. Feeding of XAD-2 caused substantial decrease of total serum cholesterol and of the cholesterol of the apo B-containing lipoproteins (50%). Atherogenesis, which was induced by mechanical injury to the arterial wall, greatly decreased (p < 0.01) in animals fed with 10% XAD-2 supplement in their diet. Average lesions volume of 4.2 +/- 2.0 mm3 per aorta was observed in animals maintained on XAD-2 diet, in comparison to 15.42 +/- 3.3 mm3 in animals maintained on regular diet. The animals maintained on XAD-2 showed elevated activity of hepatic HMG-CoA reductase. The activity of this enzyme was 3.2 fold that obtained from livers of control animals.