Brain interstitial fluid glutamine homeostasis is controlled by blood-brain barrier SLC7A5/LAT1 amino acid transporter.

ABSTRACT: L-glutamine (Gln) is the most abundant amino acid in plasma and cerebrospinal fluid and a precursor for the main central nervous system excitatory (L-glutamate) and inhibitory (γ-aminobutyric acid (GABA)) neurotransmitters. Concentrations of Gln and 13 other brain interstitial fluid amino acids were measured in awake, freely moving mice by hippocampal microdialysis using an extrapolation to zero flow rate method. Interstitial fluid levels for all amino acids including Gln were ∼5-10 times lower than in cerebrospinal fluid. Although the large increase in plasma Gln by intraperitoneal (IP) injection of ¹⁵N₂-labeled Gln (hGln) did not increase total interstitial fluid Gln, low levels of hGln were detected in microdialysis samples. Competitive inhibition of system A (SLC3

SUBMITTER: Dolgodilina E 

PROVIDER: S-EPMC5094305 | biostudies-literature | 2016 Nov

REPOSITORIES: biostudies-literature