A simplified procedure for the in vitro assay of the initial linear rate of the reaction of lecithin-cholesterol acyltransferase in human serum.
A simple sensitive method for the determination of the initial rate of the reaction of lecithin-cholesterol acyltransferase by equilibrating [3H]cholesterol with unesterified cholesterol of human serum is described. The resulting serum is incubated for various time periods at 37 degrees C and the increase of the label in the cholesterol ester fraction is measured. The labeling is effected by a filter paper method in which a paper strip containing the labeled cholesterol is placed in serum at 4 degrees C, thereby preventing the formation of labeled cholesterol esters by the action of the enzyme. The rate of the reaction was linear up to 30 min.