PHOSPHATIDYL CHOLINE EXCHANGE IN MODEL LIPOPROTEINS - APPLICATION OF PHOSPHOLIPIDS MICELLES IMMOBILIZED ON APOHDL-SEPHAROSE

A phosphatidyl choline (PC) exchange between apoHDL/PC micellar complexes in solution and the same complexes immobilized on Sepharose was studied. The PC ex change in buffer was represented in terms of pseudo first order reversible process. The first order constants for the unidirectional efflux of PC from apoHDL/PC-Sepharose (k1) and for the unidirectional efflux of PC from apoHDL/PC complexes (k2) were equal to (0.45+/-0.2).10(-3) and (1.35+/-0.2).10(-3) min-1, respectively. The k1 values showed the Arrhenius dependence on the temperature within range 278-323K. Plasma serum proteins facilitated the PC efflux from apoHDL/PC-Sepharose being additional acceptors of PC. These data allow use of apoHDL/PC-Sepharose for correcting lipid plasma composition in vitro.