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Anti-Hebbian long-term potentiation in the hippocampal feedback inhibitory circuit.

ABSTRACT: Long-term potentiation (LTP), which approximates Hebb's postulate of associative learning, typically requires depolarization-dependent glutamate receptors of the NMDA (N-methyl-D-aspartate) subtype. However, in some neurons, LTP depends instead on calcium-permeable AMPA-type receptors. This is paradoxical because intracellular polyamines block such receptors during depolarization. We report that LTP at synapses on hippocampal interneurons mediating feedback inhibition is "anti-Hebbian":Itis induced by presynaptic activity but prevented by postsynaptic depolarization. Anti-Hebbian LTP may occur in interneurons that are silent during periods of intense pyramidal cell firing, such as sharp waves, and lead to their altered activation during theta activity.

SUBMITTER: Lamsa KP

PROVIDER: S-EPMC3369266 | biostudies-literature | 2007 Mar

REPOSITORIES: biostudies-literature

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Anti-Hebbian long-term potentiation in the hippocampal feedback inhibitory circuit.

Lamsa Karri P KP Heeroma Joost H JH Somogyi Peter P Rusakov Dmitri A DA Kullmann Dimitri M DM

Science (New York, N.Y.) 20070301 5816

Long-term potentiation (LTP), which approximates Hebb's postulate of associative learning, typically requires depolarization-dependent glutamate receptors of the NMDA (N-methyl-D-aspartate) subtype. However, in some neurons, LTP depends instead on calcium-permeable AMPA-type receptors. This is paradoxical because intracellular polyamines block such receptors during depolarization. We report that LTP at synapses on hippocampal interneurons mediating feedback inhibition is "anti-Hebbian":Itis indu ...[more]

PMID: 17332410

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