Pyroglutamate stimulates Na+ -dependent glutamate transport across the blood-brain barrier

FEBS Lett. 2006 Aug 7;580(18):4382-6. doi: 10.1016/j.febslet.2006.06.097. Epub 2006 Jul 10.


Regulation of Na(+)-dependent glutamate transport was studied in isolated luminal and abluminal plasma membranes derived from the bovine blood-brain barrier. Abluminal membranes have Na(+)-dependent glutamate transporters while luminal membranes have facilitative transporters. This organization allows glutamate to be actively removed from brain. gamma-Glutamyl transpeptidase, the first enzyme of the gamma-glutamyl cycle (GGC), is on the luminal membrane. Pyroglutamate (oxoproline), an intracellular product of GGC, stimulated Na(+)-dependent transport of glutamate by 46%, whereas facilitative glutamate uptake in luminal membranes was inhibited. This relationship between GGC and glutamate transporters may be part of a regulatory mechanism that accelerates glutamate removal from brain.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Biological Transport, Active / drug effects
  • Blood-Brain Barrier / metabolism*
  • Cattle
  • Cell Membrane / metabolism
  • Glutamic Acid / metabolism*
  • Pyrrolidonecarboxylic Acid / pharmacology*
  • Sodium / metabolism*


  • Glutamic Acid
  • Sodium
  • Pyrrolidonecarboxylic Acid