Essential fatty acid deficiency lowers the activity of the acetylated low density lipoprotein receptor of rat peritoneal macrophages.
We compared phospholipid fatty acid composition, cholesterol ester accumulation, and receptor-mediated binding, internalization, and degradation of acetylated low-density lipoprotein (acetyl-LDL) in cultured peritoneal macrophages from rats fed an essential fatty acid deficient or control diet. The deficient diet increased the 5,8,11-eicosatrienoic acid and decreased the omega 6 fatty acid content of macrophage phospholipid relative to control. The deficient diet did not affect macrophage uptake of [1-14C]oleate; however, it lowered the accumulation of intracellular labelled cholesteroyl oleate to 66% of the control. This effect was attributed to a diminution of the specific binding of acetyl-LDL, and not to acetyl-LDL internalization nor to degradation. The results demonstrate the sensitivity of the acetyl-LDL receptor to changes in its membrane environment, brought about through dietary means.
Gavino
G R
GR
Département de nutrition, Faculté de médecine, Université de Montréal (Québec), Canada.
Levy
E
E
Gavino
V C
VC
D000107:Acetylation; D000818:Animals; D002788:Cholesterol Esters / Q000378:metabolism; D008078:Cholesterol, LDL / Q000378:metabolism*; D004195:Disease Models, Animal; D005228:Fatty Acids, Essential / Q000172:deficiency*; D007700:Kinetics; D008264:Macrophages / Q000378:metabolism*; D008297:Male; D019301:Oleic Acid; D009829:Oleic Acids / Q000378:metabolism*; D010743:Phospholipids / Q000032:analysis; D011869:Radioligand Assay; D051381:Rats; D011919:Rats, Inbred Strains; D011973:Receptors, LDL / Q000378:metabolism*
D002788:Cholesterol Esters; D008078:Cholesterol, LDL; D005228:Fatty Acids, Essential; D009829:Oleic Acids; D010743:Phospholipids; D011973:Receptors, LDL; D019301:Oleic Acid