title: Proton gradient-dependent transport of glycine in rabbit renal brush-border membrane vesicles.
abstract: This study describes evidence for the existence of a H+/glycine symport system in rabbit renal brush-border membrane vesicles. An inward proton gradient stimulates glycine transport across the brush-border membrane, and this H+-driven glycine uptake is attenuated by the protonophore carbonyl cyanide p-trifluoromethoxyphenylhydrazone. It is a positive rheogenic process, i.e. the H+-dependent glycine uptake is further enhanced by an intravesicular negative potential. Glycine uptake is stimulated to a lesser degree by an inward Na+ gradient. H+-dependent glycine uptake is inhibited by sarcosine (69%), an analog amino acid, imino acids (proline 81%, hydroxy proline 67%), and beta-alanine (31%), but not by neutral (L-leucine) or basic (L-lysine) amino acids. The results demonstrate that H+ glycine co-transport system in rabbit renal brush-border membrane vesicles is a carrier-mediated electrogenic process and that transport is shared by imino acids and partially by beta-alanine.
authors.affiliation: Department of Medicine, Veterans Administration Medical Center, Milwaukee, Wisconsin.
authors.forename: V M
authors.initials: VM
authors.lastname: Rajendran
authors.forename: J A
authors.initials: JA
authors.lastname: Barry
authors.forename: J G
authors.initials: JG
authors.lastname: Kleinman
authors.forename: K
authors.initials: K
authors.lastname: Ramaswamy
mesh_terms: D000596:Amino Acids / Q000494:pharmacology; D000818:Animals; D001692:Biological Transport / Q000187:drug effects; D002250:Carbon Radioisotopes; D002259:Carbonyl Cyanide p-Trifluoromethoxyphenylhydrazone / Q000494:pharmacology; D005260:Female; D005998:Glycine / Q000378:metabolism*; D007672:Kidney Cortex / Q000378:metabolism*; D007700:Kinetics; D008871:Microvilli / Q000378:metabolism*; D011522:Protons; D011817:Rabbits
chemical_list: D000596:Amino Acids; D002250:Carbon Radioisotopes; D011522:Protons; D002259:Carbonyl Cyanide p-Trifluoromethoxyphenylhydrazone; D005998:Glycine