A simple and reliable method is described for the determination of leucine flux in vivo using two stable isotopes of leucine and gas chromatography—mass spectrometry (GCMS). [6,6,6-2H3]Leucine is administered as a primed-dose constant infusion in vivo and dl-[2H7]leucine is added to plasma as an internal standard. Plasma leucine concentration and moles per cent enrichment of [2H3]leucine can be determined simultaneously by GCMS and selected ion monitoring. Leucine flux calculated from the [6,6,6-2H3]leucine data was nearly identical to that obtained with l-[U-14C]leucine in dogs. This method is readily applicable to the study of leucine metabolism in humans of all ages and laboratory animals.
|Original language||English (US)|
|Number of pages||7|
|Journal||Journal of Chromatography B: Biomedical Applications|
|State||Published - 1980|
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