estimates of the steady-state distribution ratios of two nonmetabolizable amino acids , alpha-aminoisobutyric acid and aminocyclopentane carboxylic acid ( cycloleucine ) , between plasma and cerebrospinal fluid were made with a view to establishing whether or not the low values found with metabolizable amino acids , such as glycine or leucine , could be accounted for by uptake and metabolism by the brain .
C0002520
amino
C0017890
glycine