Article date: 1989/4/6
PubMed ID: 2564640
Journal name: Nature (ISSN: 0028-0836)
Long-term potentiation (LTP) in the hippocampus is widely studied as the mechanisms involved in its induction and maintenance are believed to underlie fundamental properties of learning and memory in vertebrates. Most synapses that exhibit LTP use an excitatory amino-acid neurotransmitter that acts on two types of receptor, the N-methyl-D-aspartate (NMDA) and quisqualate receptors. The quisqualate receptor mediates the fast synaptic response evoked by low-frequency stimulation, whereas the NMDA receptor system is activated transiently by tetanic stimulation, leading to the induction of LTP. The events responsible for maintaining LTP once it is established are not known. We now demonstrate that the sensitivity of CA1 neurons in hippocampal slices to ionophoretically-applied quisqualate receptor ligands slowly increases following the induction of LTP. This provides direct evidence for a functional post-synaptic change and suggests that pre-synaptic mechanisms also contribute, but in a temporally distinct manner, to the maintenance of LTP.
Author List: Davies S N, Lester R A, Reymann K G, Collingridge G L
Publication Types: Journal Article; Research Support, Non-U.S. Gov't
Substances mentioned in the article: Quinoxalines; Ibotenic Acid; 6-Cyano-7-nitroquinoxaline-2,3-dione; alpha-Amino-3-hydroxy-5-methyl-4-isoxazolepropionic Acid;
Mesh terms: 6-Cyano-7-nitroquinoxaline-2,3-dione; Action Potentials; Animals; Hippocampus/physiology; Ibotenic Acid/analogs & derivatives; Quinoxalines/pharmacology; Rats; Synapses/physiology; alpha-Amino-3-hydroxy-5-methyl-4-isoxazolepropionic Acid;