Transport of salicylate in proximal tubule (S sub 2 segment) isolated from rabbit kidney

Journal Article · Fri Apr 01 00:00:00 EST 1988 · American Journal of Physiology; (USA)

OSTI ID:6749059

Schild, L; Roch-Ramel, F ^[1]

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1. Institut de Pharmacologie de l'Universite de Lausanne (Switzerland)

The secretory and the reabsorptive transport of salicylate was studied in the isolated and perfused rabbit proximal tubule (S{sub 2} segment). Salicylate secretion (J{sub sal}{sup b{yields}l}) fulfilled the criteria for a carrier-mediated transport system: J{sub sal}{sup b{yields}l} was saturable, was reversibly inhibited by probenecid, and occurred against a concentration gradient. The K{sub m} and V{sub max} for this secretory transport were 80 {mu}M and 3,200 fmol{center dot}min{sup {minus}1}{center dot}mm{sup {minus}1}, respectively. At luminal pH of 7.4 and 6.6, salicylate reabsorption (J{sub sal}{sup l{yields}b}) was low. J{sub sal}{sup l{yields}b} was stimulated by increasing the bath Pco{sub 2} or by removing basolateral HCO{sub 3}{sup {minus}}; J{sub sal}{sup l{yields}b} was inhibited by ethoxyzolamide and by SITS in the bath. The results indicate that salicylate reabsorption depends on H{sup +} secretion, consistent with reabsorption by simple nonionic diffusion. When salicylate was present in the lumen only, J{sub sal}{sup l{yields}b} increased after inhibition of the secretory transport by adding ouabain or probenecid in the bath or by lowering the bath temperature. These results are compatible with luminal recycling of salicylate, and suggest the presence of a mediated secretory transporter located at the luminal membrane.

• OSTI ID: 6749059
• Journal Information: American Journal of Physiology; (USA), Vol. 254:4; ISSN 0002-9513
• Country of Publication: United States
• Language: English

Related Subjects

59 BASIC BIOLOGICAL SCIENCES
CARBON 14 COMPOUNDS
MEMBRANE TRANSPORT
SALICYLIC ACID
TUBULES
PHYSIOLOGY
DOSE-RESPONSE RELATIONSHIPS
INULIN
MEMBRANE PROTEINS
PH VALUE
RABBITS
TRITIUM COMPOUNDS
ANIMALS
BODY
CARBOHYDRATES
CARBOXYLIC ACIDS
HYDROGEN COMPOUNDS
HYDROXY ACIDS
KIDNEYS
LABELLED COMPOUNDS
MAMMALS
ORGANIC ACIDS
ORGANIC COMPOUNDS
ORGANS
POLYSACCHARIDES
PROTEINS
SACCHARIDES
VERTEBRATES
551001* - Physiological Systems- Tracer Techniques