A method of direct measurement for the enzymatic determination of cholesteryl esters.
A direct measurement method for the enzymatic determination of cholesteryl esters (CEs) without measuring total cholesterol (TC) and free cholesterol (FC) is described. In the first step, hydrogen peroxide generated by cholesterol oxidase from FC was decomposed by catalase. In the second step, CE was measured by enzymatic determination using a colorimetric method or a fluorometric method. The measurement sensitivity of the fluorometric method was more than 20 times that of the colorimetric method. Optimal conditions of the assay were determined, and examples of measured CE in human plasma, rat liver, and cultured cells are indicated. The method of directly measuring CE was simple and has exceptional reproducibility compared with the technique of subtracting FC from TC using each measured TC and FC.
Mizoguchi
Toshimi
T
Tokyo New Drug Research Laboratories II, Pharmaceutical Division, Kowa Co. Ltd., Tokyo 189-0022, Japan. t-mizogt@kowa.co.jp
Edano
Toshiyuki
T
Koshi
Tomoyuki
T
D000818:Animals; D045744:Cell Line, Tumor; D002788:Cholesterol Esters / Q000737:chemistry*; D002789:Cholesterol Oxidase / Q000737:chemistry; D003124:Colorimetry / Q000379:methods*; D005470:Fluorometry / Q000379:methods*; D006801:Humans; D008099:Liver / Q000737:chemistry*; D008297:Male; D010949:Plasma / Q000737:chemistry*; D011549:Pseudomonas / Q000737:chemistry / Q000201:enzymology; D051381:Rats; D017207:Rats, Sprague-Dawley; D012015:Reference Standards; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D002787:Sterol Esterase / Q000737:chemistry
D002788:Cholesterol Esters; D002789:Cholesterol Oxidase; D002787:Sterol Esterase