Exposure to an Alarm Pheromone Combined with Footshock Stress Enhances Responsivity of the Medial Amygdala-Hippocampus Circuit

Carlos M. Contreras; Tania Molina-Jiménez; Ana G. Gutiérrez-García

doi:doi:10.11648/j.ajpn.20140206.11

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Exposure to an Alarm Pheromone Combined with Footshock Stress Enhances Responsivity of the Medial Amygdala-Hippocampus Circuit

Carlos M. Contreras, Tania Molina-Jiménez, Ana G. Gutiérrez-García

Published in American Journal of Psychiatry and Neuroscience (Volume 2, Issue 6)

Received: 11 November 2014 Accepted: 19 November 2014 Published: 23 November 2014

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Abstract

Alarm substances are released under stressful situations and may constitute signals that prevent other members of the group from encountering dangerous situations by producing fear. 2-Heptanone is an alarm pheromone that increases the neuronal firing rate in temporal lobe structures that are related to fear in the rat, such as the basal amygdala. A single stress session of unavoidable electric footshock or 2-heptanone sniffing increases the responsivity of the medial amygdala-hippocampus circuit, but unknown is the timing of action of simultaneous exposure to both stressors on the firing rate and responsivity of CA1-CA3 neurons identified by their connections with the medial amygdala nucleus. Twenty-four or 48 h after a single stress session, we obtained single-unit extracellular recordings. The firing rate was higher in the 48 h group. The peristimulus histogram showed an increase in the responsivity of amygdala-hippocampus neurons, which was more pronounced 48 h after a single stress session. The present results suggest an increase in the sensitivity of this circuit after a single stress session, seemingly representing a first step in the formation of emotional memories related to a conditioned response to fear.

Published in	American Journal of Psychiatry and Neuroscience (Volume 2, Issue 6)
DOI	10.11648/j.ajpn.20140206.11
Page(s)	83-89
Creative Commons	This is an Open Access article, distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution and reproduction in any medium or format, provided the original work is properly cited.
Copyright	Copyright © The Author(s), 2014. Published by Science Publishing Group

Keywords

2-heptanone, Fear, Footshock, Amygdala, Hippocampus

References

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APA Style

Carlos M. Contreras, Tania Molina-Jiménez, Ana G. Gutiérrez-García. (2014). Exposure to an Alarm Pheromone Combined with Footshock Stress Enhances Responsivity of the Medial Amygdala-Hippocampus Circuit. American Journal of Psychiatry and Neuroscience, 2(6), 83-89. https://doi.org/10.11648/j.ajpn.20140206.11

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ACS Style

Carlos M. Contreras; Tania Molina-Jiménez; Ana G. Gutiérrez-García. Exposure to an Alarm Pheromone Combined with Footshock Stress Enhances Responsivity of the Medial Amygdala-Hippocampus Circuit. Am. J. Psychiatry Neurosci. 2014, 2(6), 83-89. doi: 10.11648/j.ajpn.20140206.11

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AMA Style

Carlos M. Contreras, Tania Molina-Jiménez, Ana G. Gutiérrez-García. Exposure to an Alarm Pheromone Combined with Footshock Stress Enhances Responsivity of the Medial Amygdala-Hippocampus Circuit. Am J Psychiatry Neurosci. 2014;2(6):83-89. doi: 10.11648/j.ajpn.20140206.11

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@article{10.11648/j.ajpn.20140206.11,
  author = {Carlos M. Contreras and Tania Molina-Jiménez and Ana G. Gutiérrez-García},
  title = {Exposure to an Alarm Pheromone Combined with Footshock Stress Enhances Responsivity of the Medial Amygdala-Hippocampus Circuit},
  journal = {American Journal of Psychiatry and Neuroscience},
  volume = {2},
  number = {6},
  pages = {83-89},
  doi = {10.11648/j.ajpn.20140206.11},
  url = {https://doi.org/10.11648/j.ajpn.20140206.11},
  eprint = {https://article.sciencepublishinggroup.com/pdf/10.11648.j.ajpn.20140206.11},
  abstract = {Alarm substances are released under stressful situations and may constitute signals that prevent other members of the group from encountering dangerous situations by producing fear. 2-Heptanone is an alarm pheromone that increases the neuronal firing rate in temporal lobe structures that are related to fear in the rat, such as the basal amygdala. A single stress session of unavoidable electric footshock or 2-heptanone sniffing increases the responsivity of the medial amygdala-hippocampus circuit, but unknown is the timing of action of simultaneous exposure to both stressors on the firing rate and responsivity of CA1-CA3 neurons identified by their connections with the medial amygdala nucleus. Twenty-four or 48 h after a single stress session, we obtained single-unit extracellular recordings. The firing rate was higher in the 48 h group. The peristimulus histogram showed an increase in the responsivity of amygdala-hippocampus neurons, which was more pronounced 48 h after a single stress session. The present results suggest an increase in the sensitivity of this circuit after a single stress session, seemingly representing a first step in the formation of emotional memories related to a conditioned response to fear.},
 year = {2014}
}

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TY  - JOUR
T1  - Exposure to an Alarm Pheromone Combined with Footshock Stress Enhances Responsivity of the Medial Amygdala-Hippocampus Circuit
AU  - Carlos M. Contreras
AU  - Tania Molina-Jiménez
AU  - Ana G. Gutiérrez-García
Y1  - 2014/11/23
PY  - 2014
N1  - https://doi.org/10.11648/j.ajpn.20140206.11
DO  - 10.11648/j.ajpn.20140206.11
T2  - American Journal of Psychiatry and Neuroscience
JF  - American Journal of Psychiatry and Neuroscience
JO  - American Journal of Psychiatry and Neuroscience
SP  - 83
EP  - 89
PB  - Science Publishing Group
SN  - 2330-426X
UR  - https://doi.org/10.11648/j.ajpn.20140206.11
AB  - Alarm substances are released under stressful situations and may constitute signals that prevent other members of the group from encountering dangerous situations by producing fear. 2-Heptanone is an alarm pheromone that increases the neuronal firing rate in temporal lobe structures that are related to fear in the rat, such as the basal amygdala. A single stress session of unavoidable electric footshock or 2-heptanone sniffing increases the responsivity of the medial amygdala-hippocampus circuit, but unknown is the timing of action of simultaneous exposure to both stressors on the firing rate and responsivity of CA1-CA3 neurons identified by their connections with the medial amygdala nucleus. Twenty-four or 48 h after a single stress session, we obtained single-unit extracellular recordings. The firing rate was higher in the 48 h group. The peristimulus histogram showed an increase in the responsivity of amygdala-hippocampus neurons, which was more pronounced 48 h after a single stress session. The present results suggest an increase in the sensitivity of this circuit after a single stress session, seemingly representing a first step in the formation of emotional memories related to a conditioned response to fear.
VL  - 2
IS  - 6
ER  -

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Author Information

Carlos M. Contreras

Unidad Periférica del Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México, Xalapa, Veracruz, 91190, México
Tania Molina-Jiménez

Laboratorio de Neurofarmacología, Instituto de Neuroetología, Universidad Veracruzana, Xalapa, Veracruz, 91190, México
Ana G. Gutiérrez-García

Laboratorio de Neurofarmacología, Instituto de Neuroetología, Universidad Veracruzana, Xalapa, Veracruz, 91190, México

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APA Style

Carlos M. Contreras, Tania Molina-Jiménez, Ana G. Gutiérrez-García. (2014). Exposure to an Alarm Pheromone Combined with Footshock Stress Enhances Responsivity of the Medial Amygdala-Hippocampus Circuit. American Journal of Psychiatry and Neuroscience, 2(6), 83-89. https://doi.org/10.11648/j.ajpn.20140206.11

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ACS Style

Carlos M. Contreras; Tania Molina-Jiménez; Ana G. Gutiérrez-García. Exposure to an Alarm Pheromone Combined with Footshock Stress Enhances Responsivity of the Medial Amygdala-Hippocampus Circuit. Am. J. Psychiatry Neurosci. 2014, 2(6), 83-89. doi: 10.11648/j.ajpn.20140206.11

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AMA Style

Carlos M. Contreras, Tania Molina-Jiménez, Ana G. Gutiérrez-García. Exposure to an Alarm Pheromone Combined with Footshock Stress Enhances Responsivity of the Medial Amygdala-Hippocampus Circuit. Am J Psychiatry Neurosci. 2014;2(6):83-89. doi: 10.11648/j.ajpn.20140206.11

Copy | Download

@article{10.11648/j.ajpn.20140206.11,
  author = {Carlos M. Contreras and Tania Molina-Jiménez and Ana G. Gutiérrez-García},
  title = {Exposure to an Alarm Pheromone Combined with Footshock Stress Enhances Responsivity of the Medial Amygdala-Hippocampus Circuit},
  journal = {American Journal of Psychiatry and Neuroscience},
  volume = {2},
  number = {6},
  pages = {83-89},
  doi = {10.11648/j.ajpn.20140206.11},
  url = {https://doi.org/10.11648/j.ajpn.20140206.11},
  eprint = {https://article.sciencepublishinggroup.com/pdf/10.11648.j.ajpn.20140206.11},
  abstract = {Alarm substances are released under stressful situations and may constitute signals that prevent other members of the group from encountering dangerous situations by producing fear. 2-Heptanone is an alarm pheromone that increases the neuronal firing rate in temporal lobe structures that are related to fear in the rat, such as the basal amygdala. A single stress session of unavoidable electric footshock or 2-heptanone sniffing increases the responsivity of the medial amygdala-hippocampus circuit, but unknown is the timing of action of simultaneous exposure to both stressors on the firing rate and responsivity of CA1-CA3 neurons identified by their connections with the medial amygdala nucleus. Twenty-four or 48 h after a single stress session, we obtained single-unit extracellular recordings. The firing rate was higher in the 48 h group. The peristimulus histogram showed an increase in the responsivity of amygdala-hippocampus neurons, which was more pronounced 48 h after a single stress session. The present results suggest an increase in the sensitivity of this circuit after a single stress session, seemingly representing a first step in the formation of emotional memories related to a conditioned response to fear.},
 year = {2014}
}

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TY  - JOUR
T1  - Exposure to an Alarm Pheromone Combined with Footshock Stress Enhances Responsivity of the Medial Amygdala-Hippocampus Circuit
AU  - Carlos M. Contreras
AU  - Tania Molina-Jiménez
AU  - Ana G. Gutiérrez-García
Y1  - 2014/11/23
PY  - 2014
N1  - https://doi.org/10.11648/j.ajpn.20140206.11
DO  - 10.11648/j.ajpn.20140206.11
T2  - American Journal of Psychiatry and Neuroscience
JF  - American Journal of Psychiatry and Neuroscience
JO  - American Journal of Psychiatry and Neuroscience
SP  - 83
EP  - 89
PB  - Science Publishing Group
SN  - 2330-426X
UR  - https://doi.org/10.11648/j.ajpn.20140206.11
AB  - Alarm substances are released under stressful situations and may constitute signals that prevent other members of the group from encountering dangerous situations by producing fear. 2-Heptanone is an alarm pheromone that increases the neuronal firing rate in temporal lobe structures that are related to fear in the rat, such as the basal amygdala. A single stress session of unavoidable electric footshock or 2-heptanone sniffing increases the responsivity of the medial amygdala-hippocampus circuit, but unknown is the timing of action of simultaneous exposure to both stressors on the firing rate and responsivity of CA1-CA3 neurons identified by their connections with the medial amygdala nucleus. Twenty-four or 48 h after a single stress session, we obtained single-unit extracellular recordings. The firing rate was higher in the 48 h group. The peristimulus histogram showed an increase in the responsivity of amygdala-hippocampus neurons, which was more pronounced 48 h after a single stress session. The present results suggest an increase in the sensitivity of this circuit after a single stress session, seemingly representing a first step in the formation of emotional memories related to a conditioned response to fear.
VL  - 2
IS  - 6
ER  -

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