Department of Neuroscience, Karolinska Institutet, Stockholm, Sweden.
Cell Rep. 2020 Jan 28;30(4):1178-1194.e3. doi: 10.1016/j.celrep.2019.12.095.
To understand striatal function, it is essential to know the functional organization of the numerous inputs targeting the diverse population of striatal neurons. Using optogenetics, we activated terminals from ipsi- or contralateral primary somatosensory cortex (S1) or primary motor cortex (M1), or thalamus while obtaining simultaneous whole-cell recordings from pairs or triplets of striatal medium spiny neurons (MSNs) and adjacent interneurons. Ipsilateral corticostriatal projections provided stronger excitation to fast-spiking interneurons (FSIs) than to MSNs and only sparse and weak excitation to low threshold-spiking interneurons (LTSIs) and cholinergic interneurons (ChINs). Projections from contralateral M1 evoked the strongest responses in LTSIs but none in ChINs, whereas thalamus provided the strongest excitation to ChINs but none to LTSIs. In addition, inputs varied in their glutamate receptor composition and their short-term plasticity. Our data revealed a highly selective organization of excitatory striatal afferents, which is determined by both pre- and postsynaptic neuronal identity.
要理解纹状体的功能，了解众多针对纹状体神经元的不同群体的输入的功能组织是至关重要的。我们使用光遗传学激活同侧或对侧初级体感皮层（S1）或初级运动皮层（M1）或丘脑的末端，同时从成对或成组的纹状体中间神经元（MSNs）和相邻的中间神经元中获得全细胞记录。同侧皮质纹状体投射对快速放电中间神经元（FSIs）的兴奋性强于对 MSNs 的兴奋性，对低阈值放电中间神经元（LTSIs）和胆碱能中间神经元（ChINs）的兴奋性稀疏而微弱。来自对侧 M1 的投射在 LTSIs 中引起最强的反应，但在 ChINs 中没有引起反应，而丘脑对 ChINs 引起最强的兴奋，但对 LTSIs 没有引起兴奋。此外，输入在其谷氨酸受体组成和短期可塑性方面存在差异。我们的数据揭示了兴奋性纹状体传入的高度选择性组织，这是由突触前和突触后神经元身份共同决定的。
