ABSTRACT
Large amounts of glutamine, glutamate, and gamma aminobutryic acid (GABA) are present in the human brain, and both plasma and cerebrospinal fluid (CSF) contain high concentrations of glutamine. Plasma contains readily measurable concentrations of glutamate, and much smaller concentrations of glutamate and GABA are present in human CSF. Interpretation of the significance of altered levels of glutamine, glutamate, or GABA in human diseases requires reliable information as to what the normal values are during life and how these values may be altered in tissues following death. Glutamine concentrations are sometimes found to be elevated in the plasma and CSF of patients given certain anticonvulsant drugs, especially in infants and children treated with phenobarbitone or primidone. GABA content is abnormal in the brain in many human neurological and psychiatric disorders, as shown by quantitative measurements of this amino acid in the autopsied brain. Dialysis encephalopathy has not yet been treated with a GABA-T inhibitor, but it might respond favorably.
