Inhibition of Cholesterol Absorption by Oxidized Cholesterol in Rats.

The effects on cholesterol absorption of oxidized cholesterols were studied in lymph-cannulated rats. When a single emulsified lipid meal containing a tracer amount of [C-14]cholesterol with either 50 mg cholesterol or 50 mg oxidized cholesterol mixture was administered intragastrically, the lymphatic absorption of cholesterol for 24 h was 33.1 +/- 6.3 and 21.7 +/- 8.6%, respectively. Moreover, oxidized cholesterols also inhibited the absorption of triolein (85.9 +/- 3.2% and 59.5 +/- 18.8%). The observation may be of use since the ingestion of oxidized cholesterols tends to be increasing.