Low concentrations of N-methyl-D-aspartate inhibit the induction of long-term potentiation in rat hippocampal slices.
We have examined the effects of excitatory amino acids on tetanus-induced long-term potentiation (LTP) in the CA1 region of rat hippocampal slices. Agonists acting at N-methyl-D-aspartate (NMDA) receptors, including NMDA, aspartate and glutamate, completely block the development of LTP when administered for 5 min prior to tetanic stimulation. Additionally, and unlike the NMDA receptor antagonist 2-amino-5-phosphonovalerate (APV), NMDA blocks LTP when administered for 5 min immediately following the electrical tetanus. The effective concentrations of NMDA are subthreshold for depolarizing CA1 neurons. These results indicate that under certain conditions NMDA receptor activation prevents CA1 LTP.
Department of Psychiatry, Washington University Medical School, St. Louis, MO 63110.
Y
Y
Izumi
D B
DB
Clifford
C F
CF
Zorumski
D015763:2-Amino-5-phosphonovalerate / Q000494:pharmacology; D000596:Amino Acids / Q000502:physiology; D000818:Animals; D004558:Electric Stimulation; D005071:Evoked Potentials / Q000187:drug effects / Q000502:physiology; D006624:Hippocampus / Q000187:drug effects / Q000502:physiology*; D066298:In Vitro Techniques; D008297:Male; D016202:N-Methylaspartate / Q000494:pharmacology*; D051381:Rats; D013569:Synapses / Q000187:drug effects / Q000502:physiology
D000596:Amino Acids; D016202:N-Methylaspartate; D015763:2-Amino-5-phosphonovalerate