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The Role of the Medial and Central Amygdala in Stress-Induced Suppression of Pulsatile LH Secretion in Female Rats

Stress exerts profound inhibitory effects on reproductive function by suppressing the pulsatile release of GnRH and therefore LH. Although the mechanisms by which stressors disrupt the hypothalamic GnRH pulse generator remain to be fully elucidated, numerous studies have implicated the amygdala, esp...

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Autores principales: Lin, Yuanshao, Li, Xiaofeng, Lupi, Micol, Kinsey-Jones, James S., Shao, Bei, Lightman, Strafford L., O'Byrne, Kevin T.
Formato: Texto
Lenguaje:English
Publicado: Endocrine Society 2011
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3101805/
https://www.ncbi.nlm.nih.gov/pubmed/21159851
http://dx.doi.org/10.1210/en.2010-1003
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author Lin, Yuanshao
Li, Xiaofeng
Lupi, Micol
Kinsey-Jones, James S.
Shao, Bei
Lightman, Strafford L.
O'Byrne, Kevin T.
author_facet Lin, Yuanshao
Li, Xiaofeng
Lupi, Micol
Kinsey-Jones, James S.
Shao, Bei
Lightman, Strafford L.
O'Byrne, Kevin T.
author_sort Lin, Yuanshao
collection PubMed
description Stress exerts profound inhibitory effects on reproductive function by suppressing the pulsatile release of GnRH and therefore LH. Although the mechanisms by which stressors disrupt the hypothalamic GnRH pulse generator remain to be fully elucidated, numerous studies have implicated the amygdala, especially its medial (MeA) and central nuclei (CeA), as key modulators of the neuroendocrine response to stress. In the present study, we investigated the roles of the MeA and CeA in stress-induced suppression of LH pulses. Ovariectomized rats received bilateral ibotenic acid or sham lesions targeting the MeA or CeA; blood samples (25 μl) were taken via chronically implanted cardiac catheters every 5 min for 6 h for the measurement of LH pulses. After 2 h of baseline sampling, the rats were exposed to either: restraint (1 h), insulin-induced hypoglycemia (IIH) (0.3 U/kg, iv), or lipopolysaccharide (LPS) (25 μg/kg, iv) stress. The restraint but not IIH or LPS stress–induced suppression of LH pulses was markedly attenuated by the MeA lesions. In contrast, CeA lesioning attenuated LPS, but not restraint or IIH stress–induced suppression of LH pulses. Moreover, after restraint stress, the number of Fos-positive neurons and the percentage of glutamic acid decarboxylase(67) neurons expressing Fos was significantly greater in the GnRH-rich medial preoptic area (mPOA) of rats with intact, rather than lesioned, MeA. These data indicate that the MeA and CeA play key roles in psychogenic and immunological stress-induced suppression of the GnRH pulse generator, respectively, and the MeA-mediated effect may involve γ-aminobutyric acid ergic signaling within the mPOA.
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spelling pubmed-31018052011-05-25 The Role of the Medial and Central Amygdala in Stress-Induced Suppression of Pulsatile LH Secretion in Female Rats Lin, Yuanshao Li, Xiaofeng Lupi, Micol Kinsey-Jones, James S. Shao, Bei Lightman, Strafford L. O'Byrne, Kevin T. Endocrinology Neuroendocrinology Stress exerts profound inhibitory effects on reproductive function by suppressing the pulsatile release of GnRH and therefore LH. Although the mechanisms by which stressors disrupt the hypothalamic GnRH pulse generator remain to be fully elucidated, numerous studies have implicated the amygdala, especially its medial (MeA) and central nuclei (CeA), as key modulators of the neuroendocrine response to stress. In the present study, we investigated the roles of the MeA and CeA in stress-induced suppression of LH pulses. Ovariectomized rats received bilateral ibotenic acid or sham lesions targeting the MeA or CeA; blood samples (25 μl) were taken via chronically implanted cardiac catheters every 5 min for 6 h for the measurement of LH pulses. After 2 h of baseline sampling, the rats were exposed to either: restraint (1 h), insulin-induced hypoglycemia (IIH) (0.3 U/kg, iv), or lipopolysaccharide (LPS) (25 μg/kg, iv) stress. The restraint but not IIH or LPS stress–induced suppression of LH pulses was markedly attenuated by the MeA lesions. In contrast, CeA lesioning attenuated LPS, but not restraint or IIH stress–induced suppression of LH pulses. Moreover, after restraint stress, the number of Fos-positive neurons and the percentage of glutamic acid decarboxylase(67) neurons expressing Fos was significantly greater in the GnRH-rich medial preoptic area (mPOA) of rats with intact, rather than lesioned, MeA. These data indicate that the MeA and CeA play key roles in psychogenic and immunological stress-induced suppression of the GnRH pulse generator, respectively, and the MeA-mediated effect may involve γ-aminobutyric acid ergic signaling within the mPOA. Endocrine Society 2011-02 2010-12-15 /pmc/articles/PMC3101805/ /pubmed/21159851 http://dx.doi.org/10.1210/en.2010-1003 Text en Copyright © 2011 by The Endocrine Society This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/3.0/us/) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.
spellingShingle Neuroendocrinology
Lin, Yuanshao
Li, Xiaofeng
Lupi, Micol
Kinsey-Jones, James S.
Shao, Bei
Lightman, Strafford L.
O'Byrne, Kevin T.
The Role of the Medial and Central Amygdala in Stress-Induced Suppression of Pulsatile LH Secretion in Female Rats
title The Role of the Medial and Central Amygdala in Stress-Induced Suppression of Pulsatile LH Secretion in Female Rats
title_full The Role of the Medial and Central Amygdala in Stress-Induced Suppression of Pulsatile LH Secretion in Female Rats
title_fullStr The Role of the Medial and Central Amygdala in Stress-Induced Suppression of Pulsatile LH Secretion in Female Rats
title_full_unstemmed The Role of the Medial and Central Amygdala in Stress-Induced Suppression of Pulsatile LH Secretion in Female Rats
title_short The Role of the Medial and Central Amygdala in Stress-Induced Suppression of Pulsatile LH Secretion in Female Rats
title_sort role of the medial and central amygdala in stress-induced suppression of pulsatile lh secretion in female rats
topic Neuroendocrinology
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3101805/
https://www.ncbi.nlm.nih.gov/pubmed/21159851
http://dx.doi.org/10.1210/en.2010-1003
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