The absorption of C14-labeled epicholesterol in the rat.

The present report deals with the absorption of cholesterol and its 3-ahydroxy isomer, epicholesterol, in the rat. It is shown that cholesterol is absorbed at more than twice the rate of its stereoisomer, and that, while 50 per cent of the absorbed cholesterol recovered in lymph is esterified, none of the epicholesterol is so bound. The difference in the absorption rates of these two isomers brings to light the importance of stereoconfiguration in sterol absorption, a phenomenon previously observed for carbohydrates (1) and amino acids (2).