Measurement of daily cholesterol synthesis rates in man by assay of the fractional conversion of mevalonic acid to cholesterol

Abstract

A significant correlation was found in man between total daily cholesterol synthesis rates as determined by sterol balance measurements and the fraction of i.v. administered R [5 14C]mevalonic acid converted to cholesterol. In 30 studies it was found that the mean daily cholesterol synthesis rates estimated by sterol balance measurements ranged from 395 to 3047 mg/day, whereas the fractional conversion of mevalonate to cholesterol varied from 0.28 to 0.99. The 2 parameters correlated with a coefficient of 0.87, P < 0.001. This method for the estimation of cholesterol synthesis requires low doses of radioisotopic materials (25 μCi of [14C]mevalonate and 5 μCi of [3H]cholesterol) and less than 1 hr of the patient's time; it can be repeated at intervals of 3 wk and reflects cholesterol synthesis over a short period of time.