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Hippocampal long-term depression is required for the consolidation of spatial memory.

ABSTRACT: Although NMDA receptor (NMDAR)-dependent long-term potentiation (LTP) and long-term depression (LTD) of glutamatergic transmission are candidate mechanisms for long-term spatial memory, the precise contributions of LTP and LTD remain poorly understood. Here, we report that LTP and LTD in the hippocampal CA1 region of freely moving adult rats were prevented by NMDAR 2A (GluN2A) and 2B subunit (GluN2B) preferential antagonists, respectively. These results strongly suggest that NMDAR subtype preferential antagonists are appropriate tools to probe the roles of LTP and LTD in spatial memory. Using a Morris water maze task, the LTP-blocking GluN2A antagonist had no significant effect on any aspect of performance, whereas the LTD-blocking GluN2B antagonist impaired spatial memory consolidation. Moreover, similar spatial memory deficits were induced by inhibiting the expression of LTD with intrahippocampal infusion of a short peptide that specifically interferes with AMPA receptor endocytosis. Taken together, our findings support a functional requirement of hippocampal CA1 LTD in the consolidation of long-term spatial memory.

SUBMITTER: Ge Y

PROVIDER: S-EPMC2944752 | biostudies-literature | 2010 Sep

REPOSITORIES: biostudies-literature

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Hippocampal long-term depression is required for the consolidation of spatial memory.

Ge Yuan Y Dong Zhifang Z Bagot Rosemary C RC Howland John G JG Phillips Anthony G AG Wong Tak Pan TP Wang Yu Tian YT

Proceedings of the National Academy of Sciences of the United States of America 20100907 38

Although NMDA receptor (NMDAR)-dependent long-term potentiation (LTP) and long-term depression (LTD) of glutamatergic transmission are candidate mechanisms for long-term spatial memory, the precise contributions of LTP and LTD remain poorly understood. Here, we report that LTP and LTD in the hippocampal CA1 region of freely moving adult rats were prevented by NMDAR 2A (GluN2A) and 2B subunit (GluN2B) preferential antagonists, respectively. These results strongly suggest that NMDAR subtype prefer ...[more]

PMID: 20823230

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Dataset Information

Hippocampal long-term depression is required for the consolidation of spatial memory.

Publications

Hippocampal long-term depression is required for the consolidation of spatial memory.

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