Regulation of the sodium-potassium pump in cultured rat skeletal myotubes by intracellular sodium ions

Journal Article · Sat Jul 01 04:00:00 EDT 1989 · J. Cell. Physiol.; (United States)

DOI:https://doi.org/10.1002/jcp.1041400116· OSTI ID:5604243

Brodie, C; Sampson, S R

The properties of the Na-K pump and some of the factors controlling its amount and function were studied in rat myotubes in culture. The number of Na-K pump sites was quantified by measuring the amount of (/sup 3/H)ouabain bound to whole-cell preparations. Activity of the pump was determined by measurement of ouabain-sensitive /sup 86/Rb-uptake and component of membrane potential. Chronic treatment of myotubes with tetrodotoxin (TTX), which lowers (Na)i, decreased the number of Na-K pumps, the ouabain-sensitive 86Rb uptake, and the size of the electrogenic pump component of Em. In contrast, chronic treatment with either ouabain or veratridine, which increases (Na+)i, resulted in an elevated level of Na-K pump sites. This effect was blocked by inhibitors of protein synthesis. Neither rates of degradation nor affinity of pump sites in cells treated with TTX, veratridine, or ouabain differred from those in control cells. The number and activity of Na-K pump sites were unaffected by chronic elevation in (Ca)i or chronic depolarization. We conclude that alterations in the level in intracellular Na ions play the major role in regulation of Na-K pump synthesis in cultured mammalian skeletal muscle.

• Research Organization: Bar-Ilan Univ., Ramat-Gan (Israel)
• OSTI ID: 5604243
• Journal Information: J. Cell. Physiol.; (United States), Journal Name: J. Cell. Physiol.; (United States) Vol. 140:1; ISSN JCLLA
• Country of Publication: United States
• Language: English

Related Subjects

550201* -- Biochemistry-- Tracer Techniques
59 BASIC BIOLOGICAL SCIENCES
ACID ANHYDRASES
ALKALI METALS
ANIMALS
ATP-ASE
BETA DECAY RADIOISOTOPES
BETA-PLUS DECAY RADIOISOTOPES
BIOCHEMICAL REACTION KINETICS
CARBOHYDRATES
CARDIAC GLYCOSIDES
CARDIOTONICS
CARDIOVASCULAR AGENTS
CELL CONSTITUENTS
CELL CULTURES
CELL MEMBRANES
DRUGS
ELECTRON CAPTURE RADIOISOTOPES
ELEMENTS
ENZYMES
GLYCOSIDES
HOURS LIVING RADIOISOTOPES
HYDROLASES
INTERMEDIATE MASS NUCLEI
ISOMERIC TRANSITION ISOTOPES
ISOTOPE APPLICATIONS
ISOTOPES
KINETICS
LABELLED COMPOUNDS
MAMMALS
MEMBRANE TRANSPORT
MEMBRANES
METALS
MINUTES LIVING RADIOISOTOPES
MUSCLES
NUCLEI
ODD-EVEN NUCLEI
ORGANIC COMPOUNDS
OUABAIN
PHOSPHOHYDROLASES
POTASSIUM
RADIOISOTOPES
RATS
REACTION KINETICS
RODENTS
RUBIDIUM 81
RUBIDIUM ISOTO
SODIUM
STROPHANTHINS
TRACER TECHNIQUES
TRITIUM COMPOUNDS
VERTEBRATES