美国加州大学Kira E. Poskanzer团队取得一项新突破。他们提出了皮层星形胶质细胞局部神经递质的网络水平编码。相关论文于2024年4月17日发表在《自然》杂志上。

该研究团队以离体和体内双光子星形胶质细胞成像为主题，同时在多个时空尺度上模拟神经元神经递质输入。研究团队发现短暂的亚细胞输入的GABA和谷氨酸，导致广泛持久的星形胶质细胞Ca²⁺反应超出了个体受刺激的细胞。此外，该课题组人员发现Ca²⁺活性的一个关键——繁殖活性——区分星形胶质细胞网络对这两种主要神经递质的反应，并可能影响对未来输入的反应。

总之，他们的研究结果表明，局部的、短暂的神经递质输入是由广泛的皮层星形胶质细胞网络，在几分钟长的时间内编码的，这有助于积累证据，证明星形胶质细胞和神经元之间的大量通信，发生在缓慢的、网络层面的时空尺度上。这些发现将使未来的研究能够调查，特定星形胶质细胞Ca²⁺活性和特定功能输出之间的联系，这可以为星形胶质细胞调节神经元活动建立一致的框架。

据了解，星形胶质细胞是哺乳动物大脑中最丰富的非神经元细胞类型，是通过钙(Ca²⁺)信号响应和调节神经元活动的关键环路组成部分。星形胶质细胞Ca²⁺活性是高度异质性的，并且发生在多个时空尺度上——从快速的亚细胞活动到连接星形胶质细胞网络上缓慢的同步活动，影响许多过程。然而，驱动星形胶质细胞网络动力学的输入仍不清楚。

附：英文原文

Title: Network-level encoding of local neurotransmitters in cortical astrocytes

Author: Cahill, Michelle K., Collard, Max, Tse, Vincent, Reitman, Michael E., Etchenique, Roberto, Kirst, Christoph, Poskanzer, Kira E.

Issue&Volume: 2024-04-17

Abstract: Astrocytes, the most abundant non-neuronal cell type in the mammalian brain, are crucial circuit components that respond to and modulate neuronal activity through calcium (Ca2+) signalling1,2,3,4,5,6,7. Astrocyte Ca2+ activity is highly heterogeneous and occurs across multiple spatiotemporal scales—from fast, subcellular activity3,4 to slow, synchronized activity across connected astrocyte networks8,9,10—to influence many processes5,7,11. However, the inputs that drive astrocyte network dynamics remain unclear. Here we used ex vivo and in vivo two-photon astrocyte imaging while mimicking neuronal neurotransmitter inputs at multiple spatiotemporal scales. We find that brief, subcellular inputs of GABA and glutamate lead to widespread, long-lasting astrocyte Ca2+ responses beyond an individual stimulated cell. Further, we find that a key subset of Ca2+ activity—propagative activity—differentiates astrocyte network responses to these two main neurotransmitters, and may influence responses to future inputs. Together, our results demonstrate that local, transient neurotransmitter inputs are encoded by broad cortical astrocyte networks over a minutes-long time course, contributing to accumulating evidence that substantial astrocyte–neuron communication occurs across slow, network-level spatiotemporal scales12,13,14. These findings will enable future studies to investigate the link between specific astrocyte Ca2+ activity and specific functional outputs, which could build a consistent framework for astrocytic modulation of neuronal activity.

DOI: 10.1038/s41586-024-07311-5

Source: https://www.nature.com/articles/s41586-024-07311-5