DIFFERENTIAL EXPRESSION OF METABOTROPIC GLUTAMATE RECEPTORS IN THE HIPPOCAMPUS AND ENTORHINAL CORTEX OF THE RAT
DIFFERENTIAL EXPRESSION OF METABOTROPIC GLUTAMATE RECEPTORS IN THE HIPPOCAMPUS AND ENTORHINAL CORTEX OF THE RAT
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DOI：
10.1016/0169-328x(94)90259-3
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发表时间：
1994-02-01
期刊：
影响因子：
--
通讯作者：
YOUNG, AB
中科院分区：
文献类型：
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作者：
FOTUHI, M;STANDAERT, DG;YOUNG, AB
代谢型谷氨酸受体（mGluRs）参与海马的许多功能，包括学习和记忆。五种亚型已被分子和生物学表征。使用这五个mGluRs选择性的寡核苷酸探针原位杂交，我们发现，每个有一个独特的模式在海马和内嗅皮层的表达。mGluR 1主要在齿状回和CA 3中表达。mGluR 2在齿状回和内嗅皮层的内层中富集。mGluR 3也在这两种结构中表达，但与所有其他mGluR不同，它也在白色物质区域中发现。mGluR 4主要存在于CA 2中，而mGluR 5集中在海马和内嗅皮质的大部分区域中。这些受体的分布与其假定的下游信号转导机制的组件的比较分析表明，mGluR 5可能是mGluR的主要亚型，其介导谷氨酸在CA 1中的兴奋作用，并且可能有助于在长时程增强和缺血/缺氧损伤中发现的CA 1锥体神经元中的钙水平升高。mGluR 2和mGluR 3是谷氨酸抑制作用的主要亚型，在CA 1中不存在。因此，mGluR介导的谷氨酸兴奋作用可以发生在海马的所有区域，而mGluR介导的谷氨酸抑制作用可能仅限于齿状回和CA 3。
Metabotropic glutamate receptors (mGluRs) have been implicated in a number of hippocampal functions including learning and memory. Five subtypes have been molecularly and pharmacologically characterized. Using in situ hybridization with oligonucleotide probes selective for these five mGluRs, we have found that each has a unique pattern of expression in the hippocampus and entorhinal cortex. mGluR1 is expressed predominantly in the dentate gyrus and CA3. mGluR2 is enriched in the dentate gyrus and inner layer of the entorhinal cortex. mGluR3 is also expressed in these two structures, but unlike all the other mGluRs, is found in white matter areas as well. mGluR4 is present predominantly in CA2 while mGluR5 is concentrated in most regions of the hippocampus and entorhinal cortex. Comparative analysis of the distributions of these receptors with that of the components of their putative downstream signal transduction mechanisms suggests that mGluR5 may be the main subtype of mGluR which mediates the excitatory actions of glutamate in CA1 and could contribute to the elevation of calcium levels found in CA1 pyramidal neurons in long term potentiation and in ischemic/hypoxic injury. mGluR2 and mGluR3, the main subtypes contributing to the inhibitory actions of glutamate, are absent in CA1. Thus, the mGluR-mediated excitatory actions of glutamate can occur in all regions of the hippocampus whereas the mGluR-mediated inhibitory actions of glutamate may be restricted to the dentate gyrus and CA3.