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Pyrazinoate (PZA) is an organic anion actively reabsorbed and secreted in the mammalian kidney. In experiments with rabbit renal brush border membrane vesicles, we characterized a sodium-PZA cotransport mechanism that could be involved in reabsorption. An inwardly directed sodium gradient stimulated the influx of PZA. The sodium-dependent transport was electroneutral, suggesting a 1:1 stoichiometry. The kinetic constants for sodium-PZA cotransport were measured under initial linear flux and zero trans conditions for both sodium and PZA. The apparent Km for sodium was about 60 mM. At 90 mM sodium the apparent Km for PZA was about 1.1 mM; increasing the sodium concentration augmented the apparent affinity for PZA. Cis inhibition of sodium-dependent PZA uptake was observed by the addition of nicotinate, lactate, probenecid, succinate, beta-hydroxybutyrate, and salicylate. Urate had no effect. [14C]PZA uptake was trans stimulated by PZA itself, lactate, and nicotinate. PZA shares a transport system(s) involved in the proximal tubular reabsorption of these two anions.
M Manganel, and
F Roch-Ramel, and
H Murer
June 1992,
Pflugers Archiv : European journal of physiology,
M Manganel, and
F Roch-Ramel, and
H Murer
August 1997,
Toxicology and applied pharmacology,
M Manganel, and
F Roch-Ramel, and
H Murer
June 1987,
Biochimica et biophysica acta,
M Manganel, and
F Roch-Ramel, and
H Murer
June 1993,
The American journal of physiology,
M Manganel, and
F Roch-Ramel, and
H Murer
March 1989,
The American journal of physiology,
M Manganel, and
F Roch-Ramel, and
H Murer
January 1981,
Gastroenterology,
M Manganel, and
F Roch-Ramel, and
H Murer
January 1982,
Biochimica et biophysica acta,
M Manganel, and
F Roch-Ramel, and
H Murer
November 1986,
The Journal of biological chemistry,
M Manganel, and
F Roch-Ramel, and
H Murer
December 1997,
Biochimica et biophysica acta,
M Manganel, and
F Roch-Ramel, and
H Murer
March 1987,
The American journal of physiology,
