Cholesteryl oleyl and linoleyl ethers do not trace their ester counterparts in animals with plasma cholesteryl ester transfer activity.
Cholesteryl ethers are nonhydrolyzable tracers of cholesteryl esters. We report here that the ethers are not legitimate tracers of esters in systems involving plasma cholesteryl ester transfer activity. On intravenous injection of doubly labeled high density lipoproteins into rabbits, cholesteryl ester tracer was more rapidly transferred to other lipoprotein fractions than was cholesteryl ether tracer. In direct assays in vitro, the rate of transfer of esters was about two times that of the ether. This difference was not due to tracer impurity or lability of 3H, did not depend on the nature of the donor or acceptor lipoprotein, and was similar for cholesteryl ester transfer activities of both human and rabbit origin.
Green
S R
SR
Department of Medicine, University of California, San Diego, La Jolla 92093.
Beltz
W F
WF
Goldberg
D I
DI
Pittman
R C
RC
D000818:Animals; D002352:Carrier Proteins / Q000097:blood; D002784:Cholesterol / Q000031:analogs & derivatives* / Q000097:blood; D053480:Cholesterol Ester Transfer Proteins; D002788:Cholesterol Esters / Q000097:blood*; D006023:Glycoproteins; D066298:In Vitro Techniques; D007700:Kinetics; D008075:Lipoproteins, HDL / Q000097:blood; D011817:Rabbits; D051381:Rats
C506642:CETP protein, human; D002352:Carrier Proteins; D053480:Cholesterol Ester Transfer Proteins; D002788:Cholesterol Esters; D006023:Glycoproteins; D008075:Lipoproteins, HDL; C014409:cholesteryl oleate; C021976:cholesteryl linoleate; C023511:cholesteryl oleyl ether; C027575:cholesteryl linoleyl ether; D002784:Cholesterol