Comparison of plasma clearance of low density lipoprotein with beta-very low density lipoprotein or acetoacetylated low density lipoprotein in cholesterol-fed rabbits.
The plasma clearance and tissue distribution of radioiodinated low-density lipoprotein (LDL), beta-very low density lipoprotein (beta-VLDL), and acetoacetylated LDL were studied in cholesterol-fed rabbits. Radioiodinated LDL ([125I]LDL) was cleared more slowly than either [125I]beta-VLDL or acetoacetylated-[125I]LDL and its fractional catabolic rate was one-half that of [125I]beta-VLDL and one-ninth that of acetoacetylated-[125I]LDL. Forty-eight hours after the injection of the labeled lipoproteins, the hepatic uptake was the greatest among the organs evaluated with the uptake of [125I]LDL being one-third that of either [125I]beta-VLDL or acetoacetylated-[125I]LDL. The reduction in the hepatic uptake of LDL due to a down-regulation of the receptors would account for this retarded plasma clearance.
Asai
K
K
Department of Geriatrics, Nagoya University School of Medicine, Japan.
Hayashi
T
T
Funaki
C
C
Kuzuya
M
M
Naito
M
M
Kuzuya
F
F
D000818:Animals; D002791:Cholesterol, Dietary / Q000008:administration & dosage; D015536:Down-Regulation; D007700:Kinetics; D008077:Lipoproteins, LDL / Q000097:blood* / Q000378:metabolism; D008079:Lipoproteins, VLDL / Q000097:blood* / Q000378:metabolism; D008099:Liver / Q000378:metabolism; D008297:Male; D011817:Rabbits; D014018:Tissue Distribution
D002791:Cholesterol, Dietary; D008077:Lipoproteins, LDL; D008079:Lipoproteins, VLDL; C044102:acetoacetyl-LDL