Mullen, P, Pilati, N, Large, CH et al. (2 more authors) (2022) Kv3 channels contribute to the excitability of sub-populations of spinal cord neurons in lamina VII. eNeuro. ISSN 2373-2822
Abstract
Autonomic parasympathetic preganglionic neurons (PGN) drive contraction of the bladder during micturition but remain quiescent during bladder filling. This quiescence is postulated to be due to recurrent inhibition of PGN by fast-firing adjoining interneurons. Here, we defined four distinct neuronal types within lamina VII of the lumbosacral spinal cord, where PGN are situated, by combining whole cell patch clamp recordings with k-means clustering of a range of electrophysiological parameters. Additional morphological analysis separated these neuronal classes into parasympathetic preganglionic populations (PGN) and a fast firing interneuronal population. Kv3 channels are voltage-gated potassium channels (Kv) that allow fast and precise firing of neurons. We found that blockade of Kv3 channels by tetraethylammonium (TEA) reduced neuronal firing frequency and isolated high-voltage-activated Kv currents in the fast-firing population but had no effect in PGN populations. Furthermore, Kv3 blockade potentiated the local and descending inhibitory inputs to PGN indicating that Kv3-expressing inhibitory neurons are synaptically connected to PGN. Taken together, our data reveal that Kv3 channels are crucial for fast and regulated neuronal output of a defined population that may be involved in intrinsic spinal bladder circuits that underpin recurrent inhibition of PGN.
Metadata
Item Type: | Article |
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Authors/Creators: |
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Keywords: | Spinal cord, Kv3 channels, parasympathetic, bladder reflex |
Dates: |
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Institution: | The University of Leeds |
Academic Units: | The University of Leeds > Faculty of Biological Sciences (Leeds) > School of Biomedical Sciences (Leeds) |
Depositing User: | Symplectic Publications |
Date Deposited: | 21 Jan 2022 13:52 |
Last Modified: | 21 Jan 2022 13:52 |
Status: | Published online |
Publisher: | Society for Neuroscience |
Identification Number: | 10.1523/ENEURO.0510-21.2021 |
Open Archives Initiative ID (OAI ID): | oai:eprints.whiterose.ac.uk:182094 |