Get access

Glucose, Insulin, and Insulin-Like Growth Factor I Regulate the Glycogen Content of Astroglia-Rich Primary Cultures

Authors

  • Ralf Dringen,

    1. Physiologisch-chemisches Institut der Universität, Tübingen, F.R.G.
    Search for more papers by this author
  • Bernd Hamprecht

    Corresponding author
    1. Physiologisch-chemisches Institut der Universität, Tübingen, F.R.G.
      Address correspondence and reprint requests to Dr. B. Hamprecht at Physiologisch-chemisches Institut der Universität, Hoppe-Seyler-Straße 4, D–7400 Tübingen, F.R.G.
    Search for more papers by this author

Address correspondence and reprint requests to Dr. B. Hamprecht at Physiologisch-chemisches Institut der Universität, Hoppe-Seyler-Straße 4, D–7400 Tübingen, F.R.G.

Abstract

Abstract: The glycogen content of astroglia-rich primary cultures derived from the brains of newborn rats depends on the concentration of glucose in the culture medium. After administration of culture medium lacking glucose, the glycogen content decreases with a half-time of 7 min. Readdition of glucose results in replenishment of the glycogen stores within 2–3 h, but fully only if glucose is present in a concentration of at least 4 mM. Insulin, or the more potent insulin-like growth factor I, increases the content of glycogen ∼1.7-fold, with the half-maximal effects being attained at concentrations of 10 and 0.5 nM, respectively. These results suggest that (a) glucose or a metabolite of it and (b) insulin-like growth factor I or a closely related peptide, but not insulin, are likely to be physiological regulators of the level of glycogen in astrocytes.

Get access to the full text of this article

Ancillary