Activation of the same mGluR5 receptors in the amygdala causes divergent effects on specific versus indiscriminate fear
Abstract
Although mGluR5-antagonists prevent fear and anxiety, little is known about how the same receptor in the amygdala gives rise to both. Combining in vitro and in vivo activation of mGluR5 in rats, we identify specific changes in intrinsic excitability and synaptic plasticity in basolateral amygdala neurons that give rise to temporally distinct and mutually exclusive effects on fear-related behaviors. The immediate impact of mGluR5 activation is to produce anxiety manifested as indiscriminate fear of both tone and context. Surprisingly, this state does not interfere with the proper encoding of tone-shock associations that eventually lead to enhanced cue-specific fear. These results provide a new framework for dissecting the functional impact of amygdalar mGluR-plasticity on fear versus anxiety in health and disease.
Article and author information
Author details
Funding
Department of Atomic Energy, Government of India (NCBS-4143)
- Sumantra Chattarji
Department of Biotechnology , Ministry of Science and Technology (DBT-BT/MB-CNDS/2013)
- Sumantra Chattarji
Wadhwani Foundation
- Sumantra Chattarji
Madan and Usha Sethi Fellowship
- Sumantra Chattarji
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Reviewing Editor
- Jennifer L Raymond, Stanford School of Medicine, United States
Ethics
Animal experimentation: All animal care and experimentation procedures were approved by the Institutional Animal Ethics Committee, National Centre for Biological Sciences (Approval No: SC-5/2009) and Committee for thePurpose of Control and Supervision of Experiments on Animals, Government of India (Registration No: 109/CPCSEA).
Version history
- Received: February 2, 2017
- Accepted: May 26, 2017
- Accepted Manuscript published: May 30, 2017 (version 1)
- Accepted Manuscript updated: June 6, 2017 (version 2)
- Version of Record published: June 12, 2017 (version 3)
Copyright
© 2017, Rahman et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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