Tadashi Yoshida¹, Akira Honda², Hiroshi Miyazaki³ and Yasushi Matsuzaki²

¹Raffles Japanese Clinic, Singapore, Singapore. ²Tokyo Medical University, Kasumigaura Hospital, Ibaraki, Japan. ³Pharmax Institute, Kanagawa, Japan.

Abstract

For more than a decade, we have developed stable isotope dilution mass spectrometry methods to quantify key intermediates in cholesterol and bile acid biosynthesis, mevalonate and oxysterols, respectively. The methods are more sensitive and reproducible than conventional radioisotope (RI), gas-chromatography (GC) or high-performance liquid chromatography (HPLC) methods, so that they are applicable not only to samples from experimental animals but also to small amounts of human specimens. In this paper, we review the development of stable isotope dilution mass spectrometry for quantifying mevalonate and oxysterols in biological materials, and demonstrate the usefulness of this technique.