title: Is there facilitated uptake of fatty acids by the liver? Interpretation and analysis of experimental data.
abstract: Uptake of hydrophobic organic anions that are extensively bound to serum proteins has been a controversial issue for over 30 years. It is known that steady-state uptake is lower in the presence of binding proteins, but it is much higher than predicted on the basis of protein-ligand binding equilibrium. Several theories have been postulated to account for this observation. Recent work has shown how binding proteins are capable of enhancing the uptake rate of long-chain fatty acids by decreasing the diffusional resistance of the unstirred fluid layer. The enhanced transport via codiffusion is especially important for tightly bound ligands like long-chain fatty acids. Whether this model accounts for all experimental data or whether hepatocytes facilitate the uptake of protein-bound ligands, by for example mediating the protein-ligand dissociation rate, is not clear. We review the published reports to gain an understanding into the potential mechanism for the extraction of long-chain fatty acids. Understanding the uptake mechanism of these important metabolic substrates is vitally important in determining their overall utilization in a variety of clinical disorders as diverse as gallstones, obesity, and atherosclerosis.
authors.affiliation: Department of Pharmacology and Therapeutics, Faculty of Medicine, University of Manitoba, Winnipeg, Canada.
authors.forename: F J
authors.initials: FJ
authors.lastname: Burczynski
authors.forename: B A
authors.initials: BA
authors.lastname: Luxon
mesh_terms: D000818:Animals; D005227:Fatty Acids / Q000378:metabolism*; D006801:Humans; D008099:Liver / Q000378:metabolism*
chemical_list: D005227:Fatty Acids