Estimation of 26-hydroxycholesterol in serum by high-performance liquid chromatography and its measurement in patients with atherosclerosis.

A method for analysing 26-hydroxycholesterol (26OHC) in serum and tissue samples using solid phase extraction and high-performance liquid chromatography is reported. This procedure was used to measure the levels of 26OHC in the sera of apparently healthy subjects and of 18 patients with angiographically proven atherosclerosis. Sixteen of the patients had levels within or below the range detected in the apparently healthy subjects (125-294 ng/ml), indicating that high 26OHC levels cannot be a major factor in the development of atherosclerosis. However, when the patients and the normal subjects were combined in a group, there was a significant positive correlation (r = 0.54, P less than 0.01) between serum cholesterol and serum 26OHC, and that correlation approached significance for each of the individual groups (P = 0.06 for each group). These results suggest that there is an association between cholesterol and 26OHC levels in human serum.