MEASUREMENT OF MEVALONIC ACID IN HUMAN URINE BY BENCH-TOP GAS-CHROMATOGRAPHY MASS-SPECTROMETRY

Urinary excretion of mevalonate was reported to be correlated with end ogenous cholesterol biosynthesis. A method is described whereby mevalo nate (MVA) concentration in urine is determined by bench top gas chrom atography-mass spectrometry after extraction as mevalonolactone (MVL) and conversion to mevalonolactone mono-TMS derivative. Within- and bet ween-assay coefficients of variation were 4.02% and 8%, respectively. The mean concentration of MVA in 24-h urine collections from ten normo lipidemic urinary subjects was 203 +/- 49.6 ng/ml (range: 44-576 ng/ml ). Administration of 40 mg of Pravastatin (an HMG-CoA reductase inhibi tor) significantly decreased (approximate to 50%) the night concentrat ion of MVA in five healthy volunteers. This assay could be useful for investigation of endogenous cholesterol synthesis rate in various dysl ipidemias and in response to drug treatment.