title: Studies of L-arginine transport in bovine aortic endothelial cells.
abstract: We have previously demonstrated that p(1),p(4)-diadenosine 5'-tetraphosphate induces the release of NO and modulates the uptake of L-arginine by bovine aortic endothelial cells (BAEC) [Hilderman, R. H., and Christensen, E. F. (1998) FEBS Lett. 407, 320-324; Hilderman, R. H., Casey, T. E., and Pojoga, L. H. (2000) Arch. Biochem. Biophys. 375, 124-130]. In this communication we characterize the uptake of L-Arg by BAEC. L-Arg is transported into BAEC by at least two different transporter systems. One transporter system is protein synthesis dependent, and L-Arg transported by this system is incorporated into proteins. The second transporter system involved in L-Arg uptake is protein synthesis independent, and uptake occurs by facilitated diffusion. The L-Arg transported by facilitated diffusion is metabolized into L-argininosuccinate. Homologous and heterologous competition uptake studies were performed using a fixed concentration of radiolabeled L-Arg, L-lysine, and L-leucine with varying concentrations of competing nonradiolabeled amino acids. The results of these competition uptake studies are consistent with the protein-synthesis-dependent uptake of L-Arg taking place through a transporter system that is highly specific for L-Arg and with the facilitated diffusion uptake taking place through a transporter that is specific for L-Arg and L-Leu.
authors.affiliation: Department of Microbiology and Molecular Medicine, Clemson University, Clemson, South Carolina 29634-1909, USA.
authors.forename: T E
authors.initials: TE
authors.lastname: Casey
authors.forename: A C
authors.initials: AC
authors.lastname: Harrison
authors.forename: J K
authors.initials: JK
authors.lastname: Zimmerman
authors.forename: R H
authors.initials: RH
authors.lastname: Hilderman
mesh_terms: D000255:Adenosine Triphosphate / Q000378:metabolism / Q000494:pharmacology; D000818:Animals; D001011:Aorta / Q000166:cytology; D001120:Arginine / Q000378:metabolism* / Q000494:pharmacology; D001125:Argininosuccinic Acid / Q000378:metabolism; D001667:Binding, Competitive; D001693:Biological Transport, Active / Q000187:drug effects; D002417:Cattle; D002460:Cell Line; D003513:Cycloheximide / Q000494:pharmacology; D004058:Diffusion / Q000187:drug effects; D004305:Dose-Response Relationship, Drug; D004730:Endothelium, Vascular / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*; D007700:Kinetics; D007930:Leucine / Q000378:metabolism; D008239:Lysine / Q000378:metabolism; D014176:Protein Biosynthesis; D011500:Protein Synthesis Inhibitors / Q000494:pharmacology; D013379:Substrate Specificity
chemical_list: D011500:Protein Synthesis Inhibitors; D001125:Argininosuccinic Acid; D000255:Adenosine Triphosphate; D001120:Arginine; D003513:Cycloheximide; D007930:Leucine; D008239:Lysine