Diversity of dynamic voltage patterns in neuronal dendrites revealed by nanopipette electrophysiology

Dendrites and dendritic spines are the essential cellular compartments in neuronal communication, conveying information through transient voltage signals. Our understanding of these compartmentalized voltage dynamics in fine, distal neuronal dendrites remains poor due to the difficulties inherent to accessing and stably recording from such small, nanoscale cellular compartments for a sustained time. To overcome these challenges, we use nanopipettes that permit long and stable recordings directly from fine neuronal dendrites. We reveal a diversity of voltage dynamics present locally in dendrites, such as spontaneous voltage transients, bursting events and oscillating periods of silence and firing activity, all of which we characterized using segmentation analysis. Remarkably, we find that neuronal dendrites can display spontaneous hyperpolarisation events, and sustain transient hyperpolarised states. The voltage patterns were activity-dependent, with a stronger dependency on synaptic activity than on action potentials. Long-time recordings of fine dendritic protrusions show complex voltage dynamics that may represent a previously unexplored contribution to dendritic computations.

Automated summary

Dendrites and dendritic spines play crucial roles in neuronal communication by conveying information through voltage signals. Using nanopipettes, researchers were able to access and record voltage dynamics in fine dendrites, revealing diverse patterns such as spontaneous transients, bursting events, and oscillations. These voltage patterns were found to be more dependent on synaptic activity than on action potentials, and long-time recordings showed complex dynamics that may contribute to dendritic computations.