Validation of the Dual-Isotope Plasma Ratio Technique as a measure of Cholesterol Absorption in Old and New World Monkeys 1

Summary

Due to the experimental importance of being able to assess cholesterol absorption during the study of atherogenesis in primates, the plasma isotope ratio technique developed for rats by Zilversmit (7) was tested in New and Old World monkeys and compared with a more cumbersome procedure involving fecal collection and analysis. Although fecal analysis demonstrated an unaccountable loss of the in-tubated isotope, the comparability of the plasma ratios to absorption calculated by other methods suggests that this technique is probably as reliable as many presently available. The loss of isotope may reflect the absence of dietary cholesterol.