Astrocyte glutamine synthetase: pivotal in health and disease

Biochem Soc Trans. 2013 Dec;41(6):1518-24. doi: 10.1042/BST20130237.


The multifunctional properties of astrocytes signify their importance in brain physiology and neurological function. In addition to defining the brain architecture, astrocytes are primary elements of brain ion, pH and neurotransmitter homoeostasis. GS (glutamine synthetase), which catalyses the ATP-dependent condensation of ammonia and glutamate to form glutamine, is an enzyme particularly found in astrocytes. GS plays a pivotal role in glutamate and glutamine homoeostasis, orchestrating astrocyte glutamate uptake/release and the glutamate-glutamine cycle. Furthermore, astrocytes bear the brunt of clearing ammonia in the brain, preventing neurotoxicity. The present review depicts the central function of astrocytes, concentrating on the importance of GS in glutamate/glutamine metabolism and ammonia detoxification in health and disease.

Publication types

  • Research Support, Non-U.S. Gov't
  • Review

MeSH terms

  • Ammonia / metabolism
  • Astrocytes / enzymology*
  • Astrocytes / metabolism
  • Disease
  • Glutamate-Ammonia Ligase / metabolism*
  • Glutamic Acid / metabolism
  • Glutamine / metabolism
  • Health
  • Humans


  • Glutamine
  • Glutamic Acid
  • Ammonia
  • Glutamate-Ammonia Ligase