A new form of long-term depression in the perirhinal cortex.
We demonstrate a form of long-term depression (LTD) in the perirhinal cortex that relies on interaction between different glutamate receptors. Group II metabotropic glutamate (mGlu) receptors facilitated group I mGlu receptor-mediated increases in intracellular calcium. This facilitation plus NMDA receptor activation may be necessary for induction of LTD at resting membrane potentials. However, depolarization enhanced NMDA receptor function and removed the requirement of synergy between group I and group II mGlu receptors: under these conditions, activation of only NMDA and group I mGlu receptors was required for LTD. Such glutamate receptor interactions potentially provide new rules for synaptic plasticity. These forms of LTD occur in the perirhinal cortex, where long-term decreases in neuronal responsiveness may mediate recognition memory.
Cho
K
K
MRC Centre for Synaptic Plasticity, Dept. of Anatomy, University of Bristol, Bristol BS8 1TD, UK.
Kemp
N
N
Noel
J
J
Aggleton
J P
JP
Brown
M W
MW
Bashir
Z I
ZI
D015763:2-Amino-5-phosphonovalerate / Q000494:pharmacology; D000818:Animals; D000927:Anticonvulsants / Q000494:pharmacology; D002118:Calcium / Q000378:metabolism; D004558:Electric Stimulation; D018691:Excitatory Amino Acid Antagonists / Q000494:pharmacology; D019706:Excitatory Postsynaptic Potentials / Q000187:drug effects; D008297:Male; D008564:Membrane Potentials / Q000187:drug effects; D009433:Neural Inhibition / Q000502:physiology*; D009473:Neuronal Plasticity / Q000502:physiology; D018408:Patch-Clamp Techniques; D051381:Rats; D018094:Receptors, Metabotropic Glutamate / Q000819:agonists / Q000037:antagonists & inhibitors / Q000378:metabolism*; D016194:Receptors, N-Methyl-D-Aspartate / Q000037:antagonists & inhibitors / Q000378:metabolism; D009435:Synaptic Transmission / Q000187:drug effects / Q000502:physiology; D013702:Temporal Lobe / Q000166:cytology / Q000378:metabolism*; D013995:Time
D000927:Anticonvulsants; D018691:Excitatory Amino Acid Antagonists; D018094:Receptors, Metabotropic Glutamate; D016194:Receptors, N-Methyl-D-Aspartate; C108822:metabotropic glutamate receptor 2; C104077:metabotropic glutamate receptor type 1; D015763:2-Amino-5-phosphonovalerate; D002118:Calcium