Biomaterial Database

Indirect coupling of urate and p-aminohippurate transport to sodium in human brush-border membrane vesicles. 1996

F Roch-Ramel, and B Guisan, and L Schild

Institut de Pharmacologie et Toxicologie de l'Universite, Lausanne, Switzerland. francoise-roch-ramel@ipharm.unil.ch

[14C]urate and p-[14C]aminohippurate (PAH) uptake by human brush-border membrane vesicles (BBMV) were measured in the presence of an inwardly oriented sodium gradient. No direct sodium cotransport was observed. Indirect [14C]urate coupling to sodium transport was demonstrated by cis-stimulation of [14C]urate with nicotinate or pyrazinoate (PZA) in the extravesicular medium but not by adding lactate, alpha-ketoglutarate, or beta-hydroxybutyrate. Indirect sodium coupling of [14C]PAH uptake was observed only when alpha-ketoglutarate was added to the extravesicular medium, a mechanism similar to that of basolateral membranes. The ability for PZA (and nicotinate) to cis-stimulate urate uptake was correlated with a high apparent affinity for the urate/anion exchanger. In urate-loaded vesicles, for identical medium concentrations, [14C]PZA uptake via the urateanion exchanger was 10 times higher than [14C]lactate uptake. Such high PZA affinity for the urate exchanger, working in parallel with PZA sodium cotransport can account for the stimulation of urate reabsorption by PZA in vivo.

UI	MeSH Term	Description	Entries
D007668	Kidney	Body organ that filters blood for the secretion of URINE and that regulates ion concentrations.	Kidneys
D008871	Microvilli	Minute projections of cell membranes which greatly increase the surface area of the cell.	Brush Border,Striated Border,Border, Brush,Border, Striated,Borders, Brush,Borders, Striated,Brush Borders,Microvillus,Striated Borders
D008875	Middle Aged	An adult aged 45 - 64 years.	Middle Age
D010130	p-Aminohippuric Acid	The glycine amide of 4-aminobenzoic acid. Its sodium salt is used as a diagnostic aid to measure effective renal plasma flow (ERPF) and excretory capacity.	4-Aminohippuric Acid,para-Aminohippuric Acid,Aminohippurate Sodium,Aminohippuric Acid,Nephrotest,Sodium Para-Aminohippurate,p-Aminohippurate,4 Aminohippuric Acid,Para-Aminohippurate, Sodium,Sodium Para Aminohippurate,Sodium, Aminohippurate,p Aminohippurate,p Aminohippuric Acid,para Aminohippuric Acid
D011718	Pyrazinamide	A pyrazine that is used therapeutically as an antitubercular agent.	Tisamid
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D000368	Aged	A person 65 years of age or older. For a person older than 79 years, AGED, 80 AND OVER is available.	Elderly
D001692	Biological Transport	The movement of materials (including biochemical substances and drugs) through a biological system at the cellular level. The transport can be across cell membranes and epithelial layers. It also can occur within intracellular compartments and extracellular compartments.	Transport, Biological,Biologic Transport,Transport, Biologic
D012964	Sodium	A member of the alkali group of metals. It has the atomic symbol Na, atomic number 11, and atomic weight 23.	Sodium Ion Level,Sodium-23,Ion Level, Sodium,Level, Sodium Ion,Sodium 23
D014527	Uric Acid	An oxidation product, via XANTHINE OXIDASE, of oxypurines such as XANTHINE and HYPOXANTHINE. It is the final oxidation product of purine catabolism in humans and primates, whereas in most other mammals URATE OXIDASE further oxidizes it to ALLANTOIN.	2,6,8-Trihydroxypurine,Ammonium Acid Urate,Monosodium Urate,Monosodium Urate Monohydrate,Potassium Urate,Sodium Acid Urate,Sodium Acid Urate Monohydrate,Sodium Urate,Sodium Urate Monohydrate,Trioxopurine,Urate,Acid Urate, Ammonium,Acid Urate, Sodium,Acid, Uric,Monohydrate, Monosodium Urate,Monohydrate, Sodium Urate,Urate Monohydrate, Monosodium,Urate Monohydrate, Sodium,Urate, Ammonium Acid,Urate, Monosodium,Urate, Potassium,Urate, Sodium,Urate, Sodium Acid