levels of the proposed neurotransmitter amino acids glutamate , aspartate , gamma-aminobutyric acid ( gaba ) , and glycine were measured within the layered structures of the olfactory bulb and olfactory cortex following unilateral transections of the lateral olfactory tract or of virtually all fiber tracts of the olfactory peduncle .
C0002520
amino acids
C0017890
glycine