Very-low-density-lipoprotein secretion by isolated hepatocytes of fat-fed rats.
The very-low-density-lipoprotein secretion rate of isolated hepatocytes obtained from rats fed a high-fat diet was half that of cells from control animals. In fat-fed rats, the initial cellular uptake of [l-14C]oleate in vitro was decreased by 25%, its esterification to triacylglycerols and phospholipids by 50% and its incorporation into very-low-density-lipoprotein triacylglycerols by 70%. Exogenous oleate was not the main precursor of very-low-density lipoproteins in these animals. Lipogenesis, a minor source of very-low-density lipoproteins with the control diet in our experimental conditions, was inhibited by 84% after fat-feeding. A short-term inhibition of lipogenesis in vitro did not result in a decrease in very-low-density-lipoprotein secretion rate. The results suggest that fat-feeding decreased availability of exogenous as well as endogenous fatty acids for synthesis of very-low-density lipoproteins.
D000818:Animals; D004041:Dietary Fats / Q000494:pharmacology*; D004951:Esterification; D066298:In Vitro Techniques; D008055:Lipids / Q000096:biosynthesis; D008079:Lipoproteins, VLDL / Q000378:metabolism*; D008099:Liver / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*; D008297:Male; D019301:Oleic Acid; D009829:Oleic Acids / Q000378:metabolism; D051381:Rats; D011919:Rats, Inbred Strains
D004041:Dietary Fats; D008055:Lipids; D008079:Lipoproteins, VLDL; D009829:Oleic Acids; D019301:Oleic Acid