Vanadate and fluoride effects on Na sup + -K sup + -Cl sup minus cotransport in squid giant axon

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

OSTI ID:6749537

Altamirano, A A; Breitwieser, G E; Russel, J M ^[1]

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1. Univ. of Texas Medical Branch, Galveston (USA)

The effects of vanadate and fluoride on the Na{sup +}-K{sup +}-Cl{sup {minus}} cotransporter of the squid giant axon were assessed. In axons not treated with these agents, intracellular dialysis with ATP-depleting fluids caused bumetanide-inhibitable {sup 36}Cl influx to fall with a half time of {approximately}16 min. In the presence of either 40 {mu}M vanadate or 5 mM fluoride, the decay of bumetanide-inhibitable {sup 36}Cl influx was significantly slowed; half time for vanadate-treated axons is 45 min and four fluoride-treated axons is 37 min. These agents are not exerting their effects on Na{sup +}-K{sup +}Cl{sup {minus}} cotransport by influencing the rate of ATP depletion of the axon, since they had no effect on the ATP hydrolysis rate of an optic ganglia homogenate. We therefore suggest that these data support the hypothesis that Na{sup +}-K{sup +}-Cl{sup {minus}} cotransport in squid axons is regulated by a phosphorylation-dephosphorylation mechanism and that vanadate and fluoride reduce the rate of dephosphorylation by inhibiting a protein phosphatase.

• OSTI ID: 6749537
• 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
CHLORINE 36
MEMBRANE TRANSPORT
FLUORIDES
BIOLOGICAL EFFECTS
IONS
VANADATES
ATP
ATP-ASE
MOLLUSCS
NERVE CELLS
PHOSPHORYLATION
SODIUM CHLORIDES
ACID ANHYDRASES
ALKALI METAL COMPOUNDS
ANIMAL CELLS
ANIMALS
AQUATIC ORGANISMS
BETA DECAY RADIOISOTOPES
BETA-MINUS DECAY RADIOISOTOPES
CHARGED PARTICLES
CHEMICAL REACTIONS
CHLORIDES
CHLORINE COMPOUNDS
CHLORINE ISOTOPES
ELECTRON CAPTURE RADIOISOTOPES
ENZYMES
FLUORINE COMPOUNDS
HALIDES
HALOGEN COMPOUNDS
HYDROLASES
INVERTEBRATES
ISOTOPES
LIGHT NUCLEI
NUCLEI
NUCLEOTIDES
ODD-ODD NUCLEI
ORGANIC COMPOUNDS
OXYGEN COMPOUNDS
PHOSPHOHYDROLASES
RADIOISOTOPES
SODIUM COMPOUNDS
SOMATIC CELLS
TRANSITION ELEMENT COMPOUNDS
VANADIUM COMPOUNDS
YEARS LIVING RADIOISOTOPES
550201* - Biochemistry- Tracer Techniques