Khalil Ayoub J, Mansvelder Huibert D, Witter Laurens
Department of Integrative Neurophysiology, Amsterdam Neuroscience, Center for Neurogenomics and Cognitive Research (CNCR), Vrije Universiteit Amsterdam, 1081HV Amsterdam, the Netherlands.
Department for Developmental Origins of Disease, Wilhelmina Children's Hospital and Brain Center, University Medical Center Utrecht, 3584 EA Utrecht, the Netherlands.
iScience. 2022 Jun 18;25(7):104641. doi: 10.1016/j.isci.2022.104641. eCollection 2022 Jul 15.
The basilar pontine nuclei (bPN) are known to receive excitatory input from the entire neocortex and constitute the main source of mossy fibers to the cerebellum. Various potential inhibitory afferents have been described, but their origin, synaptic plasticity, and network function have remained elusive. Here we identify the mesodiencephalic junction (MDJ) as a prominent source of monosynaptic GABAergic inputs to the bPN. We found no evidence that these inputs converge with motor cortex (M1) inputs at the single neuron or at the local network level. Tracing the inputs to GABAergic MDJ neurons revealed inputs to these neurons from neocortical areas. Additionally, we observed little short-term synaptic facilitation or depression in afferents from the MDJ, enabling MDJ inputs to carry sign-inversed neocortical inputs. Thus, our results show a prominent source of GABAergic inhibition to the bPN that could enrich input to the cerebellar granule cell layer.
已知脑桥基底核（bPN）接收来自整个新皮层的兴奋性输入，并构成小脑苔藓纤维的主要来源。已经描述了各种潜在的抑制性传入神经，但它们的起源、突触可塑性和网络功能仍然不清楚。在这里，我们确定中脑间脑交界处（MDJ）是bPN单突触GABA能输入的一个重要来源。我们没有发现这些输入在单个神经元或局部网络水平上与运动皮层（M1）输入汇聚的证据。追踪GABA能MDJ神经元的输入发现，新皮层区域向这些神经元有输入。此外，我们观察到MDJ传入神经几乎没有短期突触易化或抑制，使得MDJ输入能够携带与新皮层输入相反的信号。因此，我们的结果显示了对bPN的一个重要GABA能抑制来源，这可能丰富小脑颗粒细胞层的输入。
