---
_id: '3515'
abstract:
- lang: eng
  text: Oscillations in neuronal networks are assumed to serve various physiological
    functions, from coordination of motor patterns to perceptual binding of sensory
    information. Here, we describe an ultra-slow oscillation (0.025 Hz) in the hippocampus.
    Extracellular and intracellular activity was recorded from the CA1 and subicular
    regions in rats of the Wistar and Sprague-Dawley strains. anesthetized with urethane.
    in a subgroup of Wistar rats (23%), spontaneous afterdischarges (4.7 +/- 1.6 s)
    occurred regularly at 40.8 +/- 15.7 s. The afterdischarge was initiated by a fast
    increase of population synchrony (100-250 Hz oscillation; “tonic” phase), followed
    by large-amplitude rhythmic waves and associated action potentials at gamma and
    beta frequency (15-50 Hz; “clonic” phase). The afterdischarges were bilaterally
    synchronous and terminated relatively abruptly without post-ictal depression.
    Single-pulse stimulation of the commissural input could trigger afterdischarges,
    but only at times when they were about to occur. Commissural stimulation evoked
    inhibitory postsynaptic potentials in pyramidal cells. However, when the stimulus
    triggered an afterdischarge, the inhibitory postsynaptic potential was absent
    and the cells remained depolarized during most of the afterdischarge. Afterdischarges
    were not observed in the Sprague-Dawley rats. Long-term analysis of interneuronal
    activity in intact, drug-free rats also revealed periodic excitability changes
    in the hippocampal network at 0.025 Hz. These findings indicate the presence of
    an ultra-slow oscillation in the hippocampal formation. The ultra-slow clock induced
    afterdischarges in susceptible animals. We hypothesize that a transient failure
    of GABAergic inhibition in a subset of Wistar rats is responsible for the emergence
    of epileptiform patterns. (C) 1999 IBRO. Published by Elsevier Science Ltd.
acknowledgement: This work was supported by the Academy of Finland (32391) and the
  NIH (NS34994, MH54671).
article_processing_charge: No
article_type: original
author:
- first_name: Markku
  full_name: Penttonen, Markku
  last_name: Penttonen
- first_name: Nina
  full_name: Nurminen, Nina
  last_name: Nurminen
- first_name: Riitta
  full_name: Miettinen, Riitta
  last_name: Miettinen
- first_name: Jouni
  full_name: Sirviö, Jouni
  last_name: Sirviö
- first_name: Darrell
  full_name: Henze, Darrell
  last_name: Henze
- first_name: Jozsef L
  full_name: Csicsvari, Jozsef L
  id: 3FA14672-F248-11E8-B48F-1D18A9856A87
  last_name: Csicsvari
  orcid: 0000-0002-5193-4036
- first_name: György
  full_name: Buzsáki, György
  last_name: Buzsáki
citation:
  ama: Penttonen M, Nurminen N, Miettinen R, et al. Ultra-slow oscillation (0.025
    Hz) triggers hippocampal afterdischarges in Wistar rats. <i>Neuroscience</i>.
    1999;94(3):735-743. doi:<a href="https://doi.org/10.1016/S0306-4522(99)00367-X">10.1016/S0306-4522(99)00367-X</a>
  apa: Penttonen, M., Nurminen, N., Miettinen, R., Sirviö, J., Henze, D., Csicsvari,
    J. L., &#38; Buzsáki, G. (1999). Ultra-slow oscillation (0.025 Hz) triggers hippocampal
    afterdischarges in Wistar rats. <i>Neuroscience</i>. Elsevier. <a href="https://doi.org/10.1016/S0306-4522(99)00367-X">https://doi.org/10.1016/S0306-4522(99)00367-X</a>
  chicago: Penttonen, Markku, Nina Nurminen, Riitta Miettinen, Jouni Sirviö, Darrell
    Henze, Jozsef L Csicsvari, and György Buzsáki. “Ultra-Slow Oscillation (0.025
    Hz) Triggers Hippocampal Afterdischarges in Wistar Rats.” <i>Neuroscience</i>.
    Elsevier, 1999. <a href="https://doi.org/10.1016/S0306-4522(99)00367-X">https://doi.org/10.1016/S0306-4522(99)00367-X</a>.
  ieee: M. Penttonen <i>et al.</i>, “Ultra-slow oscillation (0.025 Hz) triggers hippocampal
    afterdischarges in Wistar rats,” <i>Neuroscience</i>, vol. 94, no. 3. Elsevier,
    pp. 735–743, 1999.
  ista: Penttonen M, Nurminen N, Miettinen R, Sirviö J, Henze D, Csicsvari JL, Buzsáki
    G. 1999. Ultra-slow oscillation (0.025 Hz) triggers hippocampal afterdischarges
    in Wistar rats. Neuroscience. 94(3), 735–743.
  mla: Penttonen, Markku, et al. “Ultra-Slow Oscillation (0.025 Hz) Triggers Hippocampal
    Afterdischarges in Wistar Rats.” <i>Neuroscience</i>, vol. 94, no. 3, Elsevier,
    1999, pp. 735–43, doi:<a href="https://doi.org/10.1016/S0306-4522(99)00367-X">10.1016/S0306-4522(99)00367-X</a>.
  short: M. Penttonen, N. Nurminen, R. Miettinen, J. Sirviö, D. Henze, J.L. Csicsvari,
    G. Buzsáki, Neuroscience 94 (1999) 735–743.
date_created: 2018-12-11T12:03:44Z
date_published: 1999-10-01T00:00:00Z
date_updated: 2022-09-07T13:16:01Z
day: '01'
doi: 10.1016/S0306-4522(99)00367-X
extern: '1'
external_id:
  pmid:
  - '10579564'
intvolume: '        94'
issue: '3'
language:
- iso: eng
month: '10'
oa_version: None
page: 735 - 743
pmid: 1
publication: Neuroscience
publication_identifier:
  issn:
  - 0306-4522
publication_status: published
publisher: Elsevier
publist_id: '2870'
quality_controlled: '1'
scopus_import: '1'
status: public
title: Ultra-slow oscillation (0.025 Hz) triggers hippocampal afterdischarges in Wistar
  rats
type: journal_article
user_id: ea97e931-d5af-11eb-85d4-e6957dddbf17
volume: 94
year: '1999'
...