N-Acetylaspartylglutamate: possible role as the neurotransmitter of the lateral olfactory tract.
N-Acetylaspartylglutamate, an endogenous brain peptide that binds with high affinity to a subpopulation of glutamate-binding sites in rat brain, is excitatory on rat piriform cortex pyramidal cells studied in a perfused brain slice. Both the monosynaptic excitation of the pyramidal cells elicited by stimulation of the lateral olfactory tract and the response to N-acetylaspartylglutamate were blocked by DL-2-amino-4-phosphonobutyrate but not by other excitatory amino acid antagonists. Responses to glutamate and aspartate, previously considered to be candidates as the lateral olfactory tract transmitter, were unaffected by 2-amino-4-phosphonobutyrate. Three days after unilateral bulbectomy there was a significant decrease in concentrations of N-acetylaspartylglutamate as well as aspartate, N-acetylaspartate, and gamma-aminobutyrate in the pyriform cortex of the side from which the olfactory bulb had been removed. These results are consistent with the possibility that N-acetylaspartylglutamate is the endogenous transmitter of the lateral olfactory tract.
Ffrench-Mullen
J M
JM
Koller
K
K
Zaczek
R
R
Coyle
J T
JT
Hori
N
N
Carpenter
D O
DO
D000818:Animals; D001224:Aspartic Acid / Q000494:pharmacology; D002490:Central Nervous System / Q000032:analysis*; D004151:Dipeptides / Q000494:pharmacology / Q000502:physiology*; D004594:Electrophysiology; D005971:Glutamates / Q000494:pharmacology; D018698:Glutamic Acid; D009474:Neurons / Q000187:drug effects; D018377:Neurotransmitter Agents / Q000032:analysis*; D009833:Olfactory Pathways / Q000032:analysis*; D051381:Rats; D011919:Rats, Inbred Strains
D004151:Dipeptides; D005971:Glutamates; D018377:Neurotransmitter Agents; C027172:isospaglumic acid; D001224:Aspartic Acid; D018698:Glutamic Acid