The Functional Upregulation of Piriform Cortex Is Associated with Cross-Modal Plasticity in Loss of Whisker Tactile Inputs
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AbstractBackground: Cross-modal plasticity is characterized as the hypersensitivity of remaining modalities after a sensory function is lost in rodents, which ensures their awareness to environmental changes. Cellular and molecular mechanisms underlying cross-modal sensory plasticity remain unclear. We aim to study the role of different types of neurons in cross-modal plasticity.
Methodology/Principal Findings: In addition to behavioral tasks in mice, whole-cell recordings at the excitatory and inhibitory neurons, and their two-photon imaging, were conducted in piriform cortex. We produced a mouse model of cross-modal sensory plasticity that olfactory function was upregulated by trimming whiskers to deprive their sensory inputs. In the meantime of olfactory hypersensitivity, pyramidal neurons and excitatory synapses were functionally upregulated, as well as GABAergic cells and inhibitory synapses were downregulated in piriform cortex from the mice of cross-modal sensory plasticity, compared with controls. A crosswire connection between barrel cortex and piriform cortex was established in cross-modal plasticity.
Conclusion/Significance: An upregulation of pyramidal neurons and a downregulation of GABAergic neurons strengthen the activities of neuronal networks in piriform cortex, which may be responsible for olfactory hypersensitivity after a loss of whisker tactile input. This finding provides the clues for developing therapeutic strategies to promote sensory recovery and substitution.
CitationPLoS One. 2012 Aug 21; 7(8):e41986
- Upregulation of barrel GABAergic neurons is associated with cross-modal plasticity in olfactory deficit.
- Authors: Ni H, Huang L, Chen N, Zhang F, Liu D, Ge M, Guan S, Zhu Y, Wang JH
- Issue date: 2010 Oct 29
- Upregulation of excitatory neurons and downregulation of inhibitory neurons in barrel cortex are associated with loss of whisker inputs.
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- Contribution of supragranular layers to sensory processing and plasticity in adult rat barrel cortex.
- Authors: Huang W, Armstrong-James M, Rema V, Diamond ME, Ebner FF
- Issue date: 1998 Dec
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- Authors: Ramamurthy DL, Krubitzer LA
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- Piriform cortical glutamatergic and GABAergic neurons express coordinated plasticity for whisker-induced odor recall.
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- Issue date: 2017 Nov 10
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