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GPR68 deletion impairs hippocampal long-term potentiation and passive avoidance behavior.

ABSTRACT: Increased neural activities reduced pH at the synaptic cleft and interstitial spaces. Recent studies have shown that protons function as a neurotransmitter. However, it remains unclear whether protons signal through a metabotropic receptor to regulate synaptic function. Here, we showed that GPR68, a proton-sensitive GPCR, exhibited wide expression in the hippocampus, with higher expression observed in CA3 pyramidal neurons and dentate granule cells. In organotypic hippocampal slice neurons, ectopically expressed GPR68-GFP was present in dendrites, dendritic spines, and axons. Recordings in hippocampal slices isolated from GPR68-/- mice showed a reduced fiber volley at the Schaffer collateral-CA1 synapses, a reduced long-term potentiation (LTP), but unaltered paired-pulse ratio. In a step-through passive avoidance test, GPR68-/- mice exhibited reduced avoidance to the dark chamber. These findings showed that GPR68 contributes to hippocampal LTP and aversive fear memory.

SUBMITTER: Xu Y

PROVIDER: S-EPMC7526169 | biostudies-literature | 2020 Sep

REPOSITORIES: biostudies-literature

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GPR68 deletion impairs hippocampal long-term potentiation and passive avoidance behavior.

Xu Yuanyuan Y Lin Mike T MT Zha Xiang-Ming XM

Molecular brain 20200929 1

Increased neural activities reduced pH at the synaptic cleft and interstitial spaces. Recent studies have shown that protons function as a neurotransmitter. However, it remains unclear whether protons signal through a metabotropic receptor to regulate synaptic function. Here, we showed that GPR68, a proton-sensitive GPCR, exhibited wide expression in the hippocampus, with higher expression observed in CA3 pyramidal neurons and dentate granule cells. In organotypic hippocampal slice neurons, ecto ...[more]

PMID: 32993733

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Dataset Information

GPR68 deletion impairs hippocampal long-term potentiation and passive avoidance behavior.

Publications

GPR68 deletion impairs hippocampal long-term potentiation and passive avoidance behavior.

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