Effect of an acute dietary cholesterol switch on percentage cholesterol absorption. C57BL/6 mice were preconditioned for 3 weeks with 0.5% cholesterol and cholesterol absorption was measured (solid bar). The same animals were fed for additional 3 weeks with the same diet, gavaged with radiolabeled mixture, and switched immediately afterwards into 0.02% cholesterol. During the next 24 h, while consuming a 0.02% cholesterol diet, feces were collected and cholesterol absorption was measured (open bar). (Mean ± SD, n = 5.)