Recent evidence has shown that d-amino acids are present in animals and humans in high
concentrations and fulfill specific biological functions. In the central nervous system, two d-
amino acids, d-serine and d-aspartate, occur in considerable concentrations. d-Serine is
synthesized and metabolized endogenously and the same might account for d-aspartate. d-
Serine has been studied most extensively and was shown to play a role in excitatory amino
acid metabolism, being a co-agonist of the N-methyl-d-aspartate (NMDA) receptor. Insight …