The very-high-density lipoprotein fraction of rabbit plasma is rich in tissue-derived cholesterol.
When plasma from rabbits, which several weeks earlier had been infused with [3H]cholesterol, was subjected to equilibrium density gradient ultracentrifugation, the specific radioactivity of cholesterol in the very-high-density lipoprotein (VHDL) fraction (d 1.22-1.32 g/ml) was three to 8-fold greater (mean, 5.5-fold; P less than 0.001) than that in high-density lipoproteins (HDL; d 1.06-1.21 g/ml). On size exclusion chromatography of plasma, no increase in specific radioactivity was seen in particles smaller than HDL. These findings suggest that those apolipoprotein-lipid complexes that dissociate from HDL during ultracentrifugation to form the VHDL fraction contain proportionately more tissue-derived cholesterol than do those that are more tightly bound to HDL.
Department of Medicine, Bowman Gray School of Medicine, Winston-Salem, NC.
M N
MN
Nanjee
N E
NE
Miller
D000818:Animals; D002499:Centrifugation, Density Gradient; D002784:Cholesterol / Q000097:blood*; D008076:Cholesterol, HDL / Q000097:blood*; D002850:Chromatography, Gel; D008075:Lipoproteins, HDL / Q000097:blood*; D008297:Male; D011817:Rabbits
D008076:Cholesterol, HDL; D008075:Lipoproteins, HDL; C026277:very high density lipoproteins; D002784:Cholesterol