2025-09-15 ミシガン大学
Web要約 の発言:
<関連情報>
- https://news.umich.edu/u-m-scientists-discover-unique-brain-cell-that-may-hold-key-to-alzheimers-disorientation/
- https://www.sciencedirect.com/science/article/pii/S0301008225000954
脳状態を横断した角速度符号化への示唆を伴う、顆粒状後帯状皮質に対する細胞型特異的コリン作動性制御 Cell-type-specific cholinergic control of granular retrosplenial cortex with implications for angular velocity coding across brain states
Izabela Jedrasiak-Cape, Chloe Rybicki-Kler, Isla Brooks, Megha Ghosh, Ellen K.W. Brennan, Sameer Kailasa, Tyler G. Ekins, Alan Rupp, Omar J. Ahmed
Progress in Neurobiology Available onlin:e 8 July 2025
DOI:https://doi.org/10.1016/j.pneurobio.2025.102804
Highlights
- Unique cell type in granular retrosplenial cortex (RSG): the low rheobase (LR) cell
- LR cells are the most ubiquitous cell type in RSG but transcriptomically distinct
- LR cells do not fire persistently in response to cholinergic agonists
- All other RSG pyramidal cell types do fire persistently with cholinergic agonists
- Lack of persistence allows LR cells to encode head movement across brain states
Abstract
Cholinergic receptor activation enables the persistent firing of cortical pyramidal neurons, providing a key cellular basis for theories of spatial navigation involving working memory, path integration, and head direction encoding. The granular retrosplenial cortex (RSG) is important for spatially-guided behaviors, but how acetylcholine impacts RSG neurons is unknown. Here, we show that a transcriptomically, morphologically, and biophysically distinct RSG cell-type – the low-rheobase (LR) neuron – has a very distinct expression profile of cholinergic muscarinic receptors compared to all other neighboring excitatory neuronal subtypes. LR neurons do not fire persistently in response to cholinergic agonists, in stark contrast to all other principal neuronal subtypes examined within the RSG and across midline cortex. This lack of persistence allows LR neuron models to rapidly compute angular head velocity (AHV), independent of cholinergic changes seen during navigation. Thus, LR neurons can consistently compute AHV across brain states, highlighting the specialized RSG neural codes supporting navigation.
