Cargando…
Action Potential Initiation in Neocortical Inhibitory Interneurons
Action potential (AP) generation in inhibitory interneurons is critical for cortical excitation-inhibition balance and information processing. However, it remains unclear what determines AP initiation in different interneurons. We focused on two predominant interneuron types in neocortex: parvalbumi...
Autores principales: | , , , , , , , , |
---|---|
Formato: | Online Artículo Texto |
Lenguaje: | English |
Publicado: |
Public Library of Science
2014
|
Materias: | |
Acceso en línea: | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4159120/ https://www.ncbi.nlm.nih.gov/pubmed/25203314 http://dx.doi.org/10.1371/journal.pbio.1001944 |
_version_ | 1782334161270341632 |
---|---|
author | Li, Tun Tian, Cuiping Scalmani, Paolo Frassoni, Carolina Mantegazza, Massimo Wang, Yonghong Yang, Mingpo Wu, Si Shu, Yousheng |
author_facet | Li, Tun Tian, Cuiping Scalmani, Paolo Frassoni, Carolina Mantegazza, Massimo Wang, Yonghong Yang, Mingpo Wu, Si Shu, Yousheng |
author_sort | Li, Tun |
collection | PubMed |
description | Action potential (AP) generation in inhibitory interneurons is critical for cortical excitation-inhibition balance and information processing. However, it remains unclear what determines AP initiation in different interneurons. We focused on two predominant interneuron types in neocortex: parvalbumin (PV)- and somatostatin (SST)-expressing neurons. Patch-clamp recording from mouse prefrontal cortical slices showed that axonal but not somatic Na(+) channels exhibit different voltage-dependent properties. The minimal activation voltage of axonal channels in SST was substantially higher (∼7 mV) than in PV cells, consistent with differences in AP thresholds. A more mixed distribution of high- and low-threshold channel subtypes at the axon initial segment (AIS) of SST cells may lead to these differences. Surprisingly, Na(V)1.2 was found accumulated at AIS of SST but not PV cells; reducing Na(V)1.2-mediated currents in interneurons promoted recurrent network activity. Together, our results reveal the molecular identity of axonal Na(+) channels in interneurons and their contribution to AP generation and regulation of network activity. |
format | Online Article Text |
id | pubmed-4159120 |
institution | National Center for Biotechnology Information |
language | English |
publishDate | 2014 |
publisher | Public Library of Science |
record_format | MEDLINE/PubMed |
spelling | pubmed-41591202014-09-12 Action Potential Initiation in Neocortical Inhibitory Interneurons Li, Tun Tian, Cuiping Scalmani, Paolo Frassoni, Carolina Mantegazza, Massimo Wang, Yonghong Yang, Mingpo Wu, Si Shu, Yousheng PLoS Biol Research Article Action potential (AP) generation in inhibitory interneurons is critical for cortical excitation-inhibition balance and information processing. However, it remains unclear what determines AP initiation in different interneurons. We focused on two predominant interneuron types in neocortex: parvalbumin (PV)- and somatostatin (SST)-expressing neurons. Patch-clamp recording from mouse prefrontal cortical slices showed that axonal but not somatic Na(+) channels exhibit different voltage-dependent properties. The minimal activation voltage of axonal channels in SST was substantially higher (∼7 mV) than in PV cells, consistent with differences in AP thresholds. A more mixed distribution of high- and low-threshold channel subtypes at the axon initial segment (AIS) of SST cells may lead to these differences. Surprisingly, Na(V)1.2 was found accumulated at AIS of SST but not PV cells; reducing Na(V)1.2-mediated currents in interneurons promoted recurrent network activity. Together, our results reveal the molecular identity of axonal Na(+) channels in interneurons and their contribution to AP generation and regulation of network activity. Public Library of Science 2014-09-09 /pmc/articles/PMC4159120/ /pubmed/25203314 http://dx.doi.org/10.1371/journal.pbio.1001944 Text en © 2014 Li et al http://creativecommons.org/licenses/by/4.0/ This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are properly credited. |
spellingShingle | Research Article Li, Tun Tian, Cuiping Scalmani, Paolo Frassoni, Carolina Mantegazza, Massimo Wang, Yonghong Yang, Mingpo Wu, Si Shu, Yousheng Action Potential Initiation in Neocortical Inhibitory Interneurons |
title | Action Potential Initiation in Neocortical Inhibitory Interneurons |
title_full | Action Potential Initiation in Neocortical Inhibitory Interneurons |
title_fullStr | Action Potential Initiation in Neocortical Inhibitory Interneurons |
title_full_unstemmed | Action Potential Initiation in Neocortical Inhibitory Interneurons |
title_short | Action Potential Initiation in Neocortical Inhibitory Interneurons |
title_sort | action potential initiation in neocortical inhibitory interneurons |
topic | Research Article |
url | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4159120/ https://www.ncbi.nlm.nih.gov/pubmed/25203314 http://dx.doi.org/10.1371/journal.pbio.1001944 |
work_keys_str_mv | AT litun actionpotentialinitiationinneocorticalinhibitoryinterneurons AT tiancuiping actionpotentialinitiationinneocorticalinhibitoryinterneurons AT scalmanipaolo actionpotentialinitiationinneocorticalinhibitoryinterneurons AT frassonicarolina actionpotentialinitiationinneocorticalinhibitoryinterneurons AT mantegazzamassimo actionpotentialinitiationinneocorticalinhibitoryinterneurons AT wangyonghong actionpotentialinitiationinneocorticalinhibitoryinterneurons AT yangmingpo actionpotentialinitiationinneocorticalinhibitoryinterneurons AT wusi actionpotentialinitiationinneocorticalinhibitoryinterneurons AT shuyousheng actionpotentialinitiationinneocorticalinhibitoryinterneurons |