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bioRxiv · 10.1101/2024.04.05.588281

H-current modulation of cortical Up and Down states

Dalla Porta, L.·Barbero-Castillo, A.·Sanchez-Sanchez, J. M.·Cancino, N.·Sanchez-Vives, M. V.
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Abstract

Understanding the link between cellular processes and brain function remains a key challenge in neuroscience. One crucial aspect is the interplay between specific ion channels and network dynamics. This work reveals a role for h-current, a hyperpolarization-activated cationic current, in shaping cortical slow oscillations. Cortical slow oscillations exhibit rhythmic periods of activity (Up states) alternating with silent periods (Down states). By progressively reducing h-current in both cortical slices and in a computational model, we observed Up states transformed into prolonged plateaus of sustained firing, while Down states were also significantly extended. This transformation led to a five-fold reduction in oscillation frequency. In a biophysical recurrent network model, we identified the cellular mechanisms: an increased input resistance and membrane time constant, increasing neuronal responsiveness to even weak inputs. HCN channels, the molecular basis of h-current, are known neuromodulatory targets, suggesting potential pathways for dynamic control of brain rhythms.

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Dalla Porta, L., Barbero-Castillo, A., Sanchez-Sanchez, J. M., Cancino, N., Sanchez-Vives, M. V.. 2024-04-10. H-current modulation of cortical Up and Down states. https://doi.org/10.1101/2024.04.05.588281

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