Neuron populations use variable combinations of short-term feedback mechanisms to stabilize firing rate.

Autor: Sarah Pellizzari, Min Hu, Lara Amaral-Silva, Sandy E Saunders, Joseph M Santin
Jazyk: angličtina
Rok vydání: 2023
Předmět:
Zdroj: PLoS Biology, Vol 21, Iss 1, p e3001971 (2023)
Druh dokumentu: article
ISSN: 1544-9173
1545-7885
DOI: 10.1371/journal.pbio.3001971
Popis: Neurons tightly regulate firing rate and a failure to do so leads to multiple neurological disorders. Therefore, a fundamental question in neuroscience is how neurons produce reliable activity patterns for decades to generate behavior. Neurons have built-in feedback mechanisms that allow them to monitor their output and rapidly stabilize firing rate. Most work emphasizes the role of a dominant feedback system within a neuronal population for the control of moment-to-moment firing. In contrast, we find that respiratory motoneurons use 2 activity-dependent controllers in unique combinations across cells, dynamic activation of an Na+ pump subtype, and rapid potentiation of Kv7 channels. Both systems constrain firing rate by reducing excitability for up to a minute after a burst of action potentials but are recruited by different cellular signals associated with activity, increased intracellular Na+ (the Na+ pump), and membrane depolarization (Kv7 channels). Individual neurons do not simply contain equal amounts of each system. Rather, neurons under strong control of the Na+ pump are weakly regulated by Kv7 enhancement and vice versa along a continuum. Thus, each motoneuron maintains its characteristic firing rate through a unique combination of the Na+ pump and Kv7 channels, which are dynamically regulated by distinct feedback signals. These results reveal a new organizing strategy for stable circuit output involving multiple fast activity sensors scaled inversely across a neuronal population.
Databáze: Directory of Open Access Journals
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