Neurochemical Research

, Volume 25, Issue 7, pp 977–982

A Model of Inositol Compartmentation in Astrocytes Based Upon Efflux Kinetics and Slow Inositol Depletion after Uptake Inhibition

  • Marina Wolfson
  • Yuly Bersudsky
  • Elna Hertz
  • Vladimir Berkin
  • Evgeny Zinger
  • Leif Hertz
Article

DOI: 10.1023/A:1007556509371

Cite this article as:
Wolfson, M., Bersudsky, Y., Hertz, E. et al. Neurochem Res (2000) 25: 977. doi:10.1023/A:1007556509371

Abstract

Intracellular compartmentation of inositol was demonstrated in primary cultures of mouse astrocytes, incubated in isotonic medium, by determination of efflux kinetics after “loading” with [3H]inositol. Three kinetically different compartments were delineated. The largest and most slowly exchanging compartment had a halflife of ∼9 hr. This slow release leads to retention of a sizeable amount of pre-accumulated inositol in the tissue 24 hr after the onset of uptake inhibition, as confirmed by the observation that the inositol uptake inhibitor fucose caused a larger inhibition of unidirectional inositol uptake than of inositol pool size, measured as accumulated [3H]inositol after 24 hr of combined exposure to the inhibitor and the labeled isotope. Based upon the present observations and literature data, it is suggested that the large, slowly exchanging compartment is largely membrane-associated and participating in signaling via the phosphatidylinositide second messenger system, whereas inositol functioning as an osmolyte is distributed in the cytosol and located in one or both of the compartments showing a faster release.

Copyright information

© Plenum Publishing Corporation 2000

Authors and Affiliations

  • Marina Wolfson
    • 1
  • Yuly Bersudsky
    • 2
  • Elna Hertz
    • 2
  • Vladimir Berkin
    • 2
  • Evgeny Zinger
    • 2
  • Leif Hertz
    • 2
  1. 1.Department of Microbiology and Immunology and Mental Health Center, Faculty of Health SciencesBen Gurion University of the NegevBeer ShevaIsrael
  2. 2.Department of Microbiology and Immunology and Mental Health Center, Faculty of Health SciencesBen Gurion University of the NegevBeer ShevaIsrael