Influence of lactose feeding on cholesterol absorption and metabolism

Abstract

[4-¹⁴C]Cholesterol was injected intravenously in rats fed on cholesterol-enriched lactose, sucrose and stock diets. It was metabolized and excreted into the bile faster in the control cholesterol-fed group than in the two sugar-supplemented groups; in the sucrose group faster than in the lactose group. In the control group, the specific activity of cholesterol was high in the small intestine soon after oral administration of [4-¹⁴C] cholesterol, but it remained low in the plasma and liver. Conversely, it was low in the small intestine but high in the plasma and liver in the lactose group. Although the uptake of cholesterol was much greater in the intestinal wall in the control group, it did not appear to be transported easily into the plasma: the converse applied in the lactose group.

The marked hypercholesteraemia induced by the lactose-cholesterol diet might be due to decreased cholesterol metabolism and increased cholesterol absorption and transport from the intestine.