Department of Biochemistry, Microbiology and Bio-informatics, Université Laval, Axis of Cellular and Molecular Neurosciences, CRIUSMQ, Québec, PQ, Canada.
Cell Calcium. 2012 Nov;52(5):339-46. doi: 10.1016/j.ceca.2012.05.001. Epub 2012 May 30.
Information processing within neural circuits depends largely on the dynamic interactions between the principal cells and inhibitory interneurons. It is further determined by the efficacy of synaptic transmission between individual circuit elements, which is in turn tightly regulated by changes in network activity to allow for numerous adaptations to occur at a single synapse. Intracellular calcium (Ca2+) is a crucial factor in the regulation of synaptic efficacy in neuronal networks. Evidence from high-resolution imaging studies has revealed the intricacies of how Ca2+ signalling is organised in the dendrites of different cell types. Inhibitory interneurons exhibit a variety of postsynaptic Ca2+ mechanisms, which are recruited by distinct activity patterns and are responsible for the formation of functionally segregated dendritic Ca2+ microdomains. Furthermore, postsynaptic Ca2+ signals in these cells not only contribute to the induction of synaptic plasticity but also may themselves undergo different forms of plastic modifications, depending on the activity level. This compartmentalised regulation of postsynaptic Ca2+ signalling may have a significant impact on the induction of synaptic plasticity and on single-interneuron and network computations.
神经回路中的信息处理在很大程度上取决于主要细胞和抑制性中间神经元之间的动态相互作用。它进一步取决于单个回路元件之间突触传递的效率，而突触传递的效率又受到网络活动变化的紧密调节，以允许在单个突触上发生许多适应。细胞内钙（Ca2+）是神经元网络中调节突触效率的关键因素。高分辨率成像研究的证据揭示了 Ca2+信号在不同细胞类型的树突中如何组织的复杂性。抑制性中间神经元表现出多种突触后 Ca2+机制，这些机制由不同的活动模式募集，并负责形成功能上分离的树突 Ca2+微区。此外，这些细胞中的突触后 Ca2+信号不仅有助于诱导突触可塑性，而且根据活动水平，它们本身可能经历不同形式的可塑性修饰。这种突触后 Ca2+信号的分区调节可能对诱导突触可塑性以及单个中间神经元和网络计算有重大影响。
