Altered hippocampal interneuron activity precedes ictal onset
Although failure of GABAergic inhibition is a commonly hypothesized mechanism underlying seizure disorders, the series of events that precipitate a rapid shift from healthy to ictal activity remain unclear. Furthermore, the diversity of inhibitory interneuron populations poses a challenge for unders...
Main Authors: | , , , |
---|---|
Format: | Article |
Language: | English |
Published: |
eLife Sciences Publications Ltd
2018-11-01
|
Series: | eLife |
Subjects: | |
Online Access: | https://elifesciences.org/articles/40750 |
id |
doaj-049f5540b1d242dbbeb7fa91d50a74e3 |
---|---|
record_format |
Article |
spelling |
doaj-049f5540b1d242dbbeb7fa91d50a74e32021-05-05T16:15:52ZengeLife Sciences Publications LtdeLife2050-084X2018-11-01710.7554/eLife.40750Altered hippocampal interneuron activity precedes ictal onsetMitra L Miri0Martin Vinck1Rima Pant2Jessica A Cardin3https://orcid.org/0000-0002-8209-5466Department of Neuroscience, Yale University School of Medicine, New Haven, United StatesDepartment of Neuroscience, Yale University School of Medicine, New Haven, United StatesDepartment of Neuroscience, Yale University School of Medicine, New Haven, United StatesDepartment of Neuroscience, Yale University School of Medicine, New Haven, United States; Kavli Institute for Neuroscience, Yale University, New Haven, United StatesAlthough failure of GABAergic inhibition is a commonly hypothesized mechanism underlying seizure disorders, the series of events that precipitate a rapid shift from healthy to ictal activity remain unclear. Furthermore, the diversity of inhibitory interneuron populations poses a challenge for understanding local circuit interactions during seizure initiation. Using a combined optogenetic and electrophysiological approach, we examined the activity of identified mouse hippocampal interneuron classes during chemoconvulsant seizure induction in vivo. Surprisingly, synaptic inhibition from parvalbumin- (PV) and somatostatin-expressing (SST) interneurons remained intact throughout the preictal period and early ictal phase. However, these two sources of inhibition exhibited cell-type-specific differences in their preictal firing patterns and sensitivity to input. Our findings suggest that the onset of ictal activity is not associated with loss of firing by these interneurons or a failure of synaptic inhibition but is instead linked with disruptions of the respective roles these interneurons play in the hippocampal circuit.https://elifesciences.org/articles/40750seizurehippocampusinterneuronparvalbuminsomatostatin |
collection |
DOAJ |
language |
English |
format |
Article |
sources |
DOAJ |
author |
Mitra L Miri Martin Vinck Rima Pant Jessica A Cardin |
spellingShingle |
Mitra L Miri Martin Vinck Rima Pant Jessica A Cardin Altered hippocampal interneuron activity precedes ictal onset eLife seizure hippocampus interneuron parvalbumin somatostatin |
author_facet |
Mitra L Miri Martin Vinck Rima Pant Jessica A Cardin |
author_sort |
Mitra L Miri |
title |
Altered hippocampal interneuron activity precedes ictal onset |
title_short |
Altered hippocampal interneuron activity precedes ictal onset |
title_full |
Altered hippocampal interneuron activity precedes ictal onset |
title_fullStr |
Altered hippocampal interneuron activity precedes ictal onset |
title_full_unstemmed |
Altered hippocampal interneuron activity precedes ictal onset |
title_sort |
altered hippocampal interneuron activity precedes ictal onset |
publisher |
eLife Sciences Publications Ltd |
series |
eLife |
issn |
2050-084X |
publishDate |
2018-11-01 |
description |
Although failure of GABAergic inhibition is a commonly hypothesized mechanism underlying seizure disorders, the series of events that precipitate a rapid shift from healthy to ictal activity remain unclear. Furthermore, the diversity of inhibitory interneuron populations poses a challenge for understanding local circuit interactions during seizure initiation. Using a combined optogenetic and electrophysiological approach, we examined the activity of identified mouse hippocampal interneuron classes during chemoconvulsant seizure induction in vivo. Surprisingly, synaptic inhibition from parvalbumin- (PV) and somatostatin-expressing (SST) interneurons remained intact throughout the preictal period and early ictal phase. However, these two sources of inhibition exhibited cell-type-specific differences in their preictal firing patterns and sensitivity to input. Our findings suggest that the onset of ictal activity is not associated with loss of firing by these interneurons or a failure of synaptic inhibition but is instead linked with disruptions of the respective roles these interneurons play in the hippocampal circuit. |
topic |
seizure hippocampus interneuron parvalbumin somatostatin |
url |
https://elifesciences.org/articles/40750 |
work_keys_str_mv |
AT mitralmiri alteredhippocampalinterneuronactivityprecedesictalonset AT martinvinck alteredhippocampalinterneuronactivityprecedesictalonset AT rimapant alteredhippocampalinterneuronactivityprecedesictalonset AT jessicaacardin alteredhippocampalinterneuronactivityprecedesictalonset |
_version_ |
1721459381015412736 |