德国马克斯·普朗克大脑研究所Moritz Helmstaedter团队近期取得重要工作进展，他们对人类和小鼠的大脑皮层进行了连接组学的比较
研究人员使用小鼠、猕猴和人类皮层样本的三维电子显微镜成像来研究它们的细胞类型组成和突触回路结构。与小鼠相比，人类中间神经元增加了2.5倍，这被轴突连接概率的变化所补偿，因此人类锥体细胞的抑制性与兴奋性突触输入平衡没有产生相应的增加。 相反，增加的抑制创建了一个扩展的中间神经元到中间神经元网络，这是由中间神经元靶向中间神经元类型的扩展和它们对中间神经元神经支配的突触选择性的增加驱动的。 这些构成了人类皮层的关键神经元网络改变。
据了解，人类大脑皮层的神经元数量是小鼠大脑皮层的1000倍，但这些物种之间的突触回路可能存在的差异仍然知之甚少。
附：英文原文
Title: Connectomic comparison of mouse and human cortex
Author: Sahil Loomba, Jakob Straehle, Vijayan Gangadharan, Natalie Heike, Abdelrahman Khalifa, Alessandro Motta, Niansheng Ju, Meike Sievers, Jens Gempt, Hanno S. Meyer, Moritz Helmstaedter
Issue&Volume: 2022-06-23
Abstract: The human cerebral cortex houses 1,000 times more neurons than the cerebral cortex of a mouse, but the possible differences in synaptic circuits between these species are still poorly understood. We used 3-dimensional electron microscopy of mouse, macaque and human cortical samples to study their cell type composition and synaptic circuit architecture. The 2.5-fold increase in interneurons in humans compared to mouse was compensated by a change in axonal connection probabilities and therefore did not yield a commensurate increase in inhibitory-vs-excitatory synaptic input balance on human pyramidal cells. Rather, increased inhibition created an expanded interneuron-to-interneuron network, driven by an expansion of interneuron-targeting interneuron types and an increase in their synaptic selectivity for interneuron innervation. These constitute key neuronal network alterations in human cortex.
DOI: abo0924
Source: https://www.science.org/doi/10.1126/science.abo0924