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Ramos-Prats A, Matulewicz P, Edenhofer ML, Wang KY, Yeh CW, Fajardo-Serrano A, Kress M, Kummer K, Lien CC, Ferraguti F. Loss of mGlu 5 receptors in somatostatin-expressing neurons alters negative emotional states. Mol Psychiatry 2024:10.1038/s41380-024-02541-5. [PMID: 38575807 DOI: 10.1038/s41380-024-02541-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/12/2023] [Revised: 03/15/2024] [Accepted: 03/19/2024] [Indexed: 04/06/2024]
Abstract
Subtype 5 metabotropic glutamate receptors (mGlu5) are known to play an important role in regulating cognitive, social and valence systems. However, it remains largely unknown at which circuits and neuronal types mGlu5 act to influence these behavioral domains. Altered tissue- or cell-specific expression or function of mGlu5 has been proposed to contribute to the exacerbation of neuropsychiatric disorders. Here, we examined how these receptors regulate the activity of somatostatin-expressing (SST+) neurons, as well as their influence on behavior and brain rhythmic activity. Loss of mGlu5 in SST+ neurons elicited excitatory synaptic dysfunction in a region and sex-specific manner together with a range of emotional imbalances including diminished social novelty preference, reduced anxiety-like behavior and decreased freezing during retrieval of fear memories. In addition, the absence of mGlu5 in SST+ neurons during fear processing impaired theta frequency oscillatory activity in the medial prefrontal cortex and ventral hippocampus. These findings reveal a critical role of mGlu5 in controlling SST+ neurons excitability necessary for regulating negative emotional states.
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Affiliation(s)
- Arnau Ramos-Prats
- Institute of Pharmacology, Medical University of Innsbruck, Innsbruck, Austria
- Friedrich Miescher Institute for Biomedical Research, Basel, Switzerland
| | - Pawel Matulewicz
- Institute of Pharmacology, Medical University of Innsbruck, Innsbruck, Austria
| | | | - Kai-Yi Wang
- Institute of Neuroscience, National Yang Ming Chiao Tung University, Taipei, Taiwan
| | - Chia-Wei Yeh
- Institute of Neuroscience, National Yang Ming Chiao Tung University, Taipei, Taiwan
| | - Ana Fajardo-Serrano
- Institute of Pharmacology, Medical University of Innsbruck, Innsbruck, Austria
| | - Michaela Kress
- Institute of Physiology, Medical University of Innsbruck, Innsbruck, Austria
| | - Kai Kummer
- Institute of Physiology, Medical University of Innsbruck, Innsbruck, Austria
| | - Cheng-Chang Lien
- Institute of Neuroscience, National Yang Ming Chiao Tung University, Taipei, Taiwan
| | - Francesco Ferraguti
- Institute of Pharmacology, Medical University of Innsbruck, Innsbruck, Austria.
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2
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Ebrahimi Z, Kahvandi N, Shahriari E, Komaki A, Karimi SA, Naderishahab M, Sharifi M, Sarihi A. VU0155041, a positive allosteric modulator of mGluR4, in the nucleus accumbens facilitates extinction and inhibits the reinstatement of morphine-induced conditioned place preference in male rats. Brain Res Bull 2023; 197:57-64. [PMID: 36997034 DOI: 10.1016/j.brainresbull.2023.03.012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2022] [Revised: 03/21/2023] [Accepted: 03/28/2023] [Indexed: 04/01/2023]
Abstract
Nucleus accumbens (NAc) neurons appear to be at the hub of the reward circuit. New evidence suggests that the behavioural effects of morphine substances may be significantly regulated by glutamate-mediated transmission, notably by metabotropic glutamate (mGlu) receptors. Here, we examined the hypothesis that the mGlu4 receptor within that NAc has a role in the extinction and reinstatement of morphine-induced conditioned place preference (CPP). The animals received bilaterally microinjections of VU0155041, a positive allosteric modulator (PAM) and partial agonist of mGlu4 receptor, into the NAc. In Experiment 1, the rats received VU0155041 (10, 30 and 50μg/0.5μL) during the extinction period. In Experiment 2, the CPP extinguished rats received VU0155041 (10, 30 and 50μg/0.5μL) five minutes prior to the administration of morphine (1mg/kg) in order to reinstate the extinguished CPP. The results showed that the intra-accumbal administration of VU0155041 reduced the extinction period of CPP. Furthermore, the administration of VU0155041 into the NAc dose-dependently inhibited the reinstatement of CPP. The findings suggested that the mGluR4 in the NAc facilitates the extinction and inhibits the reinstatement of the morphine-induced CPP, which could be mediated by an increase in the release of extracellular glutamate.
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Affiliation(s)
- Zahra Ebrahimi
- Neurophysiology Research Center, Hamadan University of Medical Sciences, Hamadan, Iran
| | - Nazanin Kahvandi
- Department of Physiology, Faculty of Medicine, Hamadan University of Medical Sciences, Hamadan, Iran
| | - Elahe Shahriari
- Neurophysiology Research Center, Hamadan University of Medical Sciences, Hamadan, Iran; Department of Physiology, Faculty of Medicine, Hamadan University of Medical Sciences, Hamadan, Iran
| | - Alireza Komaki
- Neurophysiology Research Center, Hamadan University of Medical Sciences, Hamadan, Iran; Department of Neuroscience, School of Sciences and Advanced Technology in Medicine, Hamadan University of Medical Sciences, Hamadan, Iran
| | - Seyed Asaad Karimi
- Neurophysiology Research Center, Hamadan University of Medical Sciences, Hamadan, Iran; Department of Neuroscience, School of Sciences and Advanced Technology in Medicine, Hamadan University of Medical Sciences, Hamadan, Iran
| | - Marzieh Naderishahab
- Neurophysiology Research Center, Hamadan University of Medical Sciences, Hamadan, Iran
| | - Maryam Sharifi
- Neurophysiology Research Center, Hamadan University of Medical Sciences, Hamadan, Iran
| | - Abdolrahman Sarihi
- Neurophysiology Research Center, Hamadan University of Medical Sciences, Hamadan, Iran; Department of Neuroscience, School of Sciences and Advanced Technology in Medicine, Hamadan University of Medical Sciences, Hamadan, Iran.
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Mao LM, Mathur N, Shah K, Wang JQ. Roles of metabotropic glutamate receptor 8 in neuropsychiatric and neurological disorders. INTERNATIONAL REVIEW OF NEUROBIOLOGY 2023; 168:349-366. [PMID: 36868634 PMCID: PMC10162486 DOI: 10.1016/bs.irn.2022.10.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Metabotropic glutamate (mGlu) receptors are G protein-coupled receptors. Among eight mGlu subtypes (mGlu1-8), mGlu8 has drawn increasing attention. This subtype is localized to the presynaptic active zone of neurotransmitter release and is among the mGlu subtypes with high affinity for glutamate. As a Gi/o-coupled autoreceptor, mGlu8 inhibits glutamate release to maintain homeostasis of glutamatergic transmission. mGlu8 receptors are expressed in limbic brain regions and play a pivotal role in modulating motivation, emotion, cognition, and motor functions. Emerging evidence emphasizes the increasing clinical relevance of abnormal mGlu8 activity. Studies using mGlu8 selective agents and knockout mice have revealed the linkage of mGlu8 receptors to multiple neuropsychiatric and neurological disorders, including anxiety, epilepsy, Parkinson's disease, drug addiction, and chronic pain. Expression and function of mGlu8 receptors in some limbic structures undergo long-lasting adaptive changes in animal models of these disorders, which may contribute to the remodeling of glutamatergic transmission critical for the pathogenesis and symptomatology of brain illnesses. This review summarizes the current understanding of mGlu8 biology and the possible involvement of the receptor in several common psychiatric and neurological disorders.
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Affiliation(s)
- Li-Min Mao
- Department of Biomedical Sciences, University of Missouri-Kansas City, School of Medicine, Kansas City, MO, United States
| | - Nirav Mathur
- Department of Anesthesiology, University of Missouri-Kansas City, School of Medicine, Kansas City, MO, United States
| | - Karina Shah
- Department of Biomedical Sciences, University of Missouri-Kansas City, School of Medicine, Kansas City, MO, United States
| | - John Q Wang
- Department of Biomedical Sciences, University of Missouri-Kansas City, School of Medicine, Kansas City, MO, United States; Department of Anesthesiology, University of Missouri-Kansas City, School of Medicine, Kansas City, MO, United States.
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4
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Amygdala Intercalated Cells: Gate Keepers and Conveyors of Internal State to the Circuits of Emotion. J Neurosci 2022; 42:9098-9109. [PMID: 36639901 PMCID: PMC9761677 DOI: 10.1523/jneurosci.1176-22.2022] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2022] [Revised: 09/19/2022] [Accepted: 10/16/2022] [Indexed: 01/09/2023] Open
Abstract
Generating adaptive behavioral responses to emotionally salient stimuli requires evaluation of complex associations between multiple sensations, the surrounding context, and current internal state. Neural circuits within the amygdala parse this emotional information, undergo synaptic plasticity to reflect learned associations, and evoke appropriate responses through their projections to the brain regions orchestrating these behaviors. Information flow within the amygdala is regulated by the intercalated cells (ITCs), which are densely packed clusters of GABAergic neurons that encircle the basolateral amygdala (BLA) and provide contextually relevant feedforward inhibition of amygdala nuclei, including the central and BLA. Emerging studies have begun to delineate the unique contribution of each ITC cluster and establish ITCs as key loci of plasticity in emotional learning. In this review, we summarize the known connectivity and function of individual ITC clusters and explore how different neuromodulators conveying internal state act via ITC gates to shape emotionally motivated behavior. We propose that the behavioral state-dependent function of ITCs, their unique genetic profile, and rich expression of neuromodulator receptors make them potential therapeutic targets for disorders, such as anxiety, schizophrenia spectrum, and addiction.
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Ebrahimi Z, Kahvandi N, Komaki A, Karimi SA, Naderishahab M, Sarihi A. The role of mGlu4 receptors within the nucleus accumbens in acquisition and expression of morphine-induced conditioned place preference in male rats. BMC Neurosci 2021; 22:17. [PMID: 33743609 PMCID: PMC7981834 DOI: 10.1186/s12868-021-00627-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2020] [Accepted: 03/12/2021] [Indexed: 11/26/2022] Open
Abstract
Background Several studies have shown that glutamate neurotransmission in the nucleus accumbens (NAc) is required for the development of morphine-induced conditional place preference (CPP). In addition, metabotropic glutamate receptors (mGluRs) in NAc play important roles in the reward pathways. However, the precise role of mGluR4 in different steps of the morphine-induced CPP is less well known. In the present study the effect of bilateral intra-accumbal infusion of VU0155041, as a specific mGluR4 agonist on the acquisition and expression of morphine induced CPP in male Wistar rats was investigated. The animals were bilaterally implanted with guide cannulae above the NAc. In the first step of the study, the VU0155041 was administered at doses of 10, 30 and 50 μg/0.5 μL saline per side into the NAc during the 3 days of morphine (5 mg/kg) conditioning (acquisition) phase of morphine-induced CPP. In the second step of the study, the rats bilaterally received VU0155041 at the dose of 50 μg/0.5 μL, 5 min before the post-conditioning test in order to check the effect of VU0155041 on the expression of morphine-induced CPP. Results The results showed that the intra-accumbal injection of VU0155041 inhibits the acquisition of morphine-induced CPP in a dose dependent manner, but had no effect on expression. Conclusions The data indicated that intra-NAc administration of VU0155041 dose dependently blocks the establishment of morphine-induced CPP and reduces the rewarding properties of morphine. These effects may be related to changes in glutamate activity in the NAC and/or learning dependent mechanism of glutamate neurotransmission in reward pathway(s).
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Affiliation(s)
- Zahra Ebrahimi
- Neurophysiology Research Center, Hamadan University of Medical Sciences, Hamadan, Iran
| | - Nazanin Kahvandi
- Department of Physiology, Faculty of Medicine, Hamadan University of Medical Sciences, Hamadan, Iran
| | - Alireza Komaki
- Neurophysiology Research Center, Hamadan University of Medical Sciences, Hamadan, Iran.,Department of Neuroscience, School of Sciences and Advanced Technology in Medicine, Hamadan University of Medical Sciences, Hamadan, Iran
| | - Seyed Asaad Karimi
- Neurophysiology Research Center, Hamadan University of Medical Sciences, Hamadan, Iran.,Department of Neuroscience, School of Sciences and Advanced Technology in Medicine, Hamadan University of Medical Sciences, Hamadan, Iran
| | - Marzieh Naderishahab
- Neurophysiology Research Center, Hamadan University of Medical Sciences, Hamadan, Iran
| | - Abdolrahman Sarihi
- Neurophysiology Research Center, Hamadan University of Medical Sciences, Hamadan, Iran. .,Department of Neuroscience, School of Sciences and Advanced Technology in Medicine, Hamadan University of Medical Sciences, Hamadan, Iran.
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Kahvandi N, Ebrahimi Z, Karimi SA, Shahidi S, Salehi I, Naderishahab M, Sarihi A. The effect of the mGlu8 receptor agonist, (S)-3,4-DCPG on acquisition and expression of morphine-induced conditioned place preference in male rats. Behav Brain Funct 2021; 17:1. [PMID: 33612106 PMCID: PMC7897377 DOI: 10.1186/s12993-021-00174-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2020] [Accepted: 02/05/2021] [Indexed: 02/24/2023] Open
Abstract
Background The nucleus accumbens (NAc) plays a principal role in drug reward. It has been reported that metabotropic glutamate receptors (mGlu receptors) play a key role in the rewarding pathway(s). Previous studies have shown the vast allocation of the different types of mGlu receptors, including mGlu8 receptors, in regions that are associated with opioid rewards, such as the NAc. The aim of the present study was to evaluate the role of mGlu8 receptors within the NAc in the acquisition and expression phases of morphine induced conditioned place preference (CPP). Adult male Wistar rats were bilaterally implanted by two cannulas' in the NAc and were evaluated in a CPP paradigm. Selective mGlu8 receptor allosteric agonist (S-3,4-DCPG) was administered at doses of 0.03, 0.3, and 3 μg/0.5 μL saline per side into the NAc on both sides during the 3 days of morphine (5 mg/kg) conditioning (acquisition) phase, or before place preference test, or post-conditioning (expression) phase of morphine-induced CPP. Results The results revealed that intra-accumbal administration of S-3,4-DCPG (0.3 and 3 μg) markedly decreased the acquisition in a dose-dependent manner but had no effect on expression of morphine-induced CPP. Conclusions The findings suggest that activation of mGlu8 receptors in the NAc dose-dependently blocks the establishment of morphine-induced CPP and reduces the rewarding properties of morphine which may be related to the glutamate activity into the NAc and in reward pathway(s). These data suggest that mGlu8 receptor may be involved in conditioned morphine reward.
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Affiliation(s)
- Nazanin Kahvandi
- Neurophysiology Research Center, School of Medicine, Hamadan University of Medical Sciences, Shahid Fahmideh Street, Hamadan, Iran
| | - Zahra Ebrahimi
- Department of Physiology, Faculty of Medicine, Hamadan University of Medical Sciences, Hamadan, Iran
| | - Seyed Asaad Karimi
- Neurophysiology Research Center, School of Medicine, Hamadan University of Medical Sciences, Shahid Fahmideh Street, Hamadan, Iran.,Department of Neuroscience, School of Sciences and Advanced Technology in Medicine, Hamadan University of Medical Sciences, Hamadan, Iran
| | - Siamak Shahidi
- Neurophysiology Research Center, School of Medicine, Hamadan University of Medical Sciences, Shahid Fahmideh Street, Hamadan, Iran.,Department of Neuroscience, School of Sciences and Advanced Technology in Medicine, Hamadan University of Medical Sciences, Hamadan, Iran
| | - Iraj Salehi
- Neurophysiology Research Center, School of Medicine, Hamadan University of Medical Sciences, Shahid Fahmideh Street, Hamadan, Iran.,Department of Neuroscience, School of Sciences and Advanced Technology in Medicine, Hamadan University of Medical Sciences, Hamadan, Iran
| | - Marzieh Naderishahab
- Neurophysiology Research Center, School of Medicine, Hamadan University of Medical Sciences, Shahid Fahmideh Street, Hamadan, Iran
| | - Abdolrahman Sarihi
- Neurophysiology Research Center, School of Medicine, Hamadan University of Medical Sciences, Shahid Fahmideh Street, Hamadan, Iran. .,Department of Neuroscience, School of Sciences and Advanced Technology in Medicine, Hamadan University of Medical Sciences, Hamadan, Iran.
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7
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Boccella S, Marabese I, Guida F, Luongo L, Maione S, Palazzo E. The Modulation of Pain by Metabotropic Glutamate Receptors 7 and 8 in the Dorsal Striatum. Curr Neuropharmacol 2020; 18:34-50. [PMID: 31210112 PMCID: PMC7327935 DOI: 10.2174/1570159x17666190618121859] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2019] [Revised: 04/01/2019] [Accepted: 05/31/2019] [Indexed: 12/28/2022] Open
Abstract
The dorsal striatum, apart from controlling voluntary movement, displays a recently demonstrated pain inhibition. It is connected to the descending pain modulatory system and in particular to the rostral ventromedial medulla through the medullary dorsal reticular nucleus. Diseases of the basal ganglia, such as Parkinson's disease, in addition to being characterized by motor disorders, are associated with pain and hyperactivation of the excitatory transmission. A way to counteract glutamatergic hyperactivation is through the activation of group III metabotropic glutamate receptors (mGluRs), which are located on presynaptic terminals inhibiting neurotransmitter release. So far the mGluRs of group III have been the least investigated, owing to a lack of selective tools. More recently, selective ligands for each mGluR of group III, in particular positive and negative allosteric modulators, have been developed and the role of each subtype is starting to emerge. The neuroprotective potential of group III mGluRs in pathological conditions, such as those characterized by elevate glutamate, has been recently shown. In the dorsal striatum, mGluR7 and mGluR8 are located at glutamatergic corticostriatal terminals and their stimulation inhibits pain in pathological conditions such as neuropathic pain. The two receptors in the dorsal striatum have instead a different role in pain control in normal conditions. This review will discuss recent results focusing on the contribution of mGluR7 and mGluR8 in the dorsal striatal control of pain. The role of mGluR4, whose antiparkinsonian activity is widely reported, will also be addressed.
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Affiliation(s)
- Serena Boccella
- Department of Experimental Medicine, Pharmacology Division, University of Campania "L. Vanvitelli", Via Costantinopoli 16, 80138 Naples, Italy
| | - Ida Marabese
- Department of Experimental Medicine, Pharmacology Division, University of Campania "L. Vanvitelli", Via Costantinopoli 16, 80138 Naples, Italy
| | - Francesca Guida
- Department of Experimental Medicine, Pharmacology Division, University of Campania "L. Vanvitelli", Via Costantinopoli 16, 80138 Naples, Italy
| | - Livio Luongo
- Department of Experimental Medicine, Pharmacology Division, University of Campania "L. Vanvitelli", Via Costantinopoli 16, 80138 Naples, Italy
| | - Sabatino Maione
- Department of Experimental Medicine, Pharmacology Division, University of Campania "L. Vanvitelli", Via Costantinopoli 16, 80138 Naples, Italy
| | - Enza Palazzo
- Department of Experimental Medicine, Pharmacology Division, University of Campania "L. Vanvitelli", Via Costantinopoli 16, 80138 Naples, Italy
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Kasugai Y, Vogel E, Hörtnagl H, Schönherr S, Paradiso E, Hauschild M, Göbel G, Milenkovic I, Peterschmitt Y, Tasan R, Sperk G, Shigemoto R, Sieghart W, Singewald N, Lüthi A, Ferraguti F. Structural and Functional Remodeling of Amygdala GABAergic Synapses in Associative Fear Learning. Neuron 2019; 104:781-794.e4. [PMID: 31543297 DOI: 10.1016/j.neuron.2019.08.013] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2019] [Revised: 07/09/2019] [Accepted: 08/07/2019] [Indexed: 01/12/2023]
Abstract
Associative learning is thought to involve different forms of activity-dependent synaptic plasticity. Although previous studies have mostly focused on learning-related changes occurring at excitatory glutamatergic synapses, we found that associative learning, such as fear conditioning, also entails long-lasting functional and structural plasticity of GABAergic synapses onto pyramidal neurons of the murine basal amygdala. Fear conditioning-mediated structural remodeling of GABAergic synapses was associated with a change in mIPSC kinetics and an increase in the fraction of synaptic benzodiazepine-sensitive (BZD) GABAA receptors containing the α2 subunit without altering the intrasynaptic distribution and overall amount of BZD-GABAA receptors. These structural and functional synaptic changes were partly reversed by extinction training. These findings provide evidence that associative learning, such as Pavlovian fear conditioning and extinction, sculpts inhibitory synapses to regulate inhibition of active neuronal networks, a process that may tune amygdala circuit responses to threats.
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Affiliation(s)
- Yu Kasugai
- Department of Pharmacology, Medical University of Innsbruck, Innsbruck 6020, Austria
| | - Elisabeth Vogel
- Friedrich Miescher Institute for Biomedical Research, Basel 4058, Switzerland
| | - Heide Hörtnagl
- Department of Pharmacology, Medical University of Innsbruck, Innsbruck 6020, Austria
| | - Sabine Schönherr
- Department of Pharmacology, Medical University of Innsbruck, Innsbruck 6020, Austria
| | - Enrica Paradiso
- Department of Pharmacology, Medical University of Innsbruck, Innsbruck 6020, Austria
| | - Markus Hauschild
- Department of Pharmacology and Toxicology, Institute of Pharmacy and CMBI, University of Innsbruck, Innsbruck 6020, Austria
| | - Georg Göbel
- Department of Medical Statistics, Informatics and Health Economics, Medical University of Innsbruck, Innsbruck 6020, Austria
| | - Ivan Milenkovic
- Center for Brain Research, Department of Molecular Neurosciences, Medical University of Vienna, Vienna 1090, Austria
| | - Yvan Peterschmitt
- Department of Pharmacology, Medical University of Innsbruck, Innsbruck 6020, Austria; Center for Brain Research, Department of Molecular Neurosciences, Medical University of Vienna, Vienna 1090, Austria
| | - Ramon Tasan
- Department of Pharmacology, Medical University of Innsbruck, Innsbruck 6020, Austria
| | - Günther Sperk
- Department of Pharmacology, Medical University of Innsbruck, Innsbruck 6020, Austria
| | - Ryuichi Shigemoto
- Institute of Science and Technology Austria, Klosterneuburg 3400, Austria
| | - Werner Sieghart
- Center for Brain Research, Department of Molecular Neurosciences, Medical University of Vienna, Vienna 1090, Austria
| | - Nicolas Singewald
- Department of Pharmacology and Toxicology, Institute of Pharmacy and CMBI, University of Innsbruck, Innsbruck 6020, Austria
| | - Andreas Lüthi
- Friedrich Miescher Institute for Biomedical Research, Basel 4058, Switzerland; University of Basel, Basel, Switzerland
| | - Francesco Ferraguti
- Department of Pharmacology, Medical University of Innsbruck, Innsbruck 6020, Austria.
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Impact of the metabotropic glutamate receptor7 (mGlu 7) allosteric agonist, AMN082, on fear learning and memory and anxiety-like behavior. Eur J Pharmacol 2019; 858:172512. [PMID: 31260653 DOI: 10.1016/j.ejphar.2019.172512] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2019] [Revised: 06/19/2019] [Accepted: 06/27/2019] [Indexed: 12/30/2022]
Abstract
The present study was conducted to evaluate the influence of AMN082, the metabotropic glutamate receptor subtype 7 (mGlu7) allosteric agonist on different stages of memory processes connected with fear conditioning in the passive avoidance (PA) learning task in mice and negative emotional state (anxiety-like) induced by ethanol- and morphine-withdrawal in the elevated plus maze (EPM) test in rats. To perform the PA test, AMN082 (1.25, 2.5 and 5 mg/kg, i. p.) was injected to interfere with (or inhibit) acquisition, consolidation, and retrieval processes. The retention latency in each group was recorded using a step-through passive avoidance task 24 h after training. In turn, in ethanol- and morphine-withdrawal rats, the influence of AMN082 on anxiety-like behavior was estimated in the EPM test 24 h- (ethanol) and 72- h (morphine) after the last dose of repeated drug administrations. In all experimental groups, AMN082 at the dose of 5 mg/kg significantly decreased the step-through latency of long-term memory in the PA task. These AMN082 effects were reversed by MMPIP (10 mg/kg), the antagonist of mGlu7 receptor. AMN082 (2.5 and 5 mg/kg) also decreased ethanol- and morphine withdrawal-induced anxiety-like behavior in the EPM test, and this AMN082 (5 mg/kg) effect was counteracted by MMPIP pretreatment. Taken together, the results show that mGlu7 is involved in fear learning to the context and anxiety-like state connected with unpleasant experiences after ethanol- and morphine withdrawal in rodents. However, it appears that functional dissociation exists between these two AMN082 effects.
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Ferrazzo S, Gunduz-Cinar O, Stefanova N, Pollack GA, Holmes A, Schmuckermair C, Ferraguti F. Increased anxiety-like behavior following circuit-specific catecholamine denervation in mice. Neurobiol Dis 2019; 125:55-66. [PMID: 30677495 DOI: 10.1016/j.nbd.2019.01.009] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2018] [Revised: 12/18/2018] [Accepted: 01/16/2019] [Indexed: 01/27/2023] Open
Abstract
Parkinson's disease (PD) presents with a constellation of non-motor symptoms, notably increased anxiety, which are currently poorly treated and underrepresented in animal models of the disease. Human post-mortem studies report loss of catecholaminergic neurons in the pre-symptomatic phases of PD when anxiety symptoms emerge, and a large literature from rodent and human studies indicate that catecholamines are important mediators of anxiety via their modulatory effects on limbic regions such as the amygdala. On the basis of these observations, we hypothesized that anxiety in PD could result from an early loss of catecholaminergic inputs to the amygdala and/or other limbic structures. To interrogate this hypothesis, we bilaterally injected the neurotoxin 6-OHDA in the mouse basolateral amygdala (BL). This produced a restricted pattern of catecholaminergic (tyrosine-hydroxylase-labeled) denervation in the BL, intercalated cell masses and ventral hippocampus, but not the central amygdala or prefrontal cortex. We found that this circuit-specific lesion did not compromise performance on multiple measures of motor function (home cage, accelerating rotarod, beam balance, pole climbing), but did increase anxiety-like behavior in the elevated plus-maze and light-dark exploration tests. Fear behavior in the pavlovian cued conditioning and passive avoidance assays was, by contrast, unaffected; possibly due to preservation of catecholamine innervation of the central amygdala from the periaqueductal gray. These data provide some of the first evidence implicating loss of catecholaminergic neurotransmission in midbrain-amygdala circuits to increased anxiety-like behavior. Our findings offer an initial step towards identifying the neural substrates for pre-motor anxiety symptoms in PD.
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Affiliation(s)
- Sara Ferrazzo
- Department of Pharmacology, Medical University of Innsbruck, Peter Mayr Strasse 1A, 6020 Innsbruck, Austria
| | - Ozge Gunduz-Cinar
- Laboratory of Behavioral and Genomic Neuroscience, National Institute on Alcohol Abuse and Alcoholism, Bethesda, National Institutes of Health, MD, USA
| | - Nadia Stefanova
- Division of Neurobiology, Department of Neurology, Medical University of Innsbruck, Innrain 66/G2, Innsbruck, Austria
| | - Gabrielle A Pollack
- Laboratory of Behavioral and Genomic Neuroscience, National Institute on Alcohol Abuse and Alcoholism, Bethesda, National Institutes of Health, MD, USA
| | - Andrew Holmes
- Laboratory of Behavioral and Genomic Neuroscience, National Institute on Alcohol Abuse and Alcoholism, Bethesda, National Institutes of Health, MD, USA
| | - Claudia Schmuckermair
- Department of Pharmacology, Medical University of Innsbruck, Peter Mayr Strasse 1A, 6020 Innsbruck, Austria.
| | - Francesco Ferraguti
- Department of Pharmacology, Medical University of Innsbruck, Peter Mayr Strasse 1A, 6020 Innsbruck, Austria.
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11
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Cahill EN, Milton AL. Neurochemical and molecular mechanisms underlying the retrieval-extinction effect. Psychopharmacology (Berl) 2019; 236:111-132. [PMID: 30656364 PMCID: PMC6373198 DOI: 10.1007/s00213-018-5121-3] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/28/2018] [Accepted: 11/12/2018] [Indexed: 12/26/2022]
Abstract
Extinction within the reconsolidation window, or 'retrieval-extinction', has received much research interest as a possible technique for targeting the reconsolidation of maladaptive memories with a behavioural intervention. However, it remains to be determined whether the retrieval-extinction effect-a long-term reduction in fear behaviour, which appears resistant to spontaneous recovery, renewal and reinstatement-depends specifically on destabilisation of the original memory (the 'reconsolidation-update' account) or represents facilitation of an extinction memory (the 'extinction-facilitation' account). We propose that comparing the neurotransmitter systems, receptors and intracellular signalling pathways recruited by reconsolidation, extinction and retrieval-extinction will provide a way of distinguishing between these accounts.
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Affiliation(s)
- Emma N Cahill
- Department of Physiology, Development and Neuroscience, University of Cambridge, Downing Site, Cambridge, CB2 3EG, UK
| | - Amy L Milton
- Department of Psychology, University of Cambridge, Downing Site, Cambridge, CB2 3EB, UK.
- Behavioural and Clinical Neuroscience Institute, Cambridge, CB2 3EB, UK.
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12
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O’Connor RM, McCafferty CP, Bravo JA, Singewald N, Holmes A, Cryan JF. Increased amygdalar metabotropic glutamate receptor 7 mRNA in a genetic mouse model of impaired fear extinction. Psychopharmacology (Berl) 2019; 236:265-272. [PMID: 30215216 PMCID: PMC6739849 DOI: 10.1007/s00213-018-5031-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/03/2018] [Accepted: 09/05/2018] [Indexed: 12/18/2022]
Abstract
RATIONALE Post-traumatic stress disorder (PTSD) is a devastating anxiety-related disorder which develops subsequent to a severe psychologically traumatic event. Only ~ 9% of people who experience such a trauma develop PTSD. It is clear that a number of factors, including genetics, influence whether an individual will develop PTSD subsequent to a trauma. The 129S1/SvImJ (S1) inbred mouse strain displays poor fear extinction and may be useful to model this specific aspect of PTSD. The metabotropic glutamate receptor 7 (mGlu7 receptor) has previously been shown to be involved in cognitive processes and anxiety-like behaviour placing it in a key position to regulate fear extinction processes. We sought to compare mGlu7 receptor mRNA levels in the S1 strain with those in the robustly extinguishing C57BL/6J (B6) inbred strain using in situ hybridisation (ISH) in three brain regions associated with fear extinction: the amygdala, hippocampus and prefrontal cortex (PFC). RESULTS Compared to the B6 strain, S1 mice had increased mGlu7 receptor mRNA levels in the lateral amygdala (LA) and basolateral amygdala (BLA) subdivisions. An increase was also seen in the hippocampal CA1 and CA3 subregions of S1 mice. No difference in mGlu7 receptor levels were seen in the central nucleus (CeA) of the amygdala, dentate gyrus (DG) of the hippocampus or prefrontal cortex. CONCLUSIONS These data show altered mGlu7 receptor expression in key brain regions associated with fear extinction in two different inbred mouse strains which differ markedly in their fear extinction behaviour. Altered mGlu7 receptor levels may contribute to the deficit fear extinction processes seen in fear extinction in the S1 strain.
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Affiliation(s)
- Richard M. O’Connor
- Department of Anatomy and Neuroscience and APC Microbiome Institute, University College Cork, Cork, Ireland,Department of Neuroscience, Icahn School of Medicine at Mount Sinai, S10-20 Hess CSM, 1470 Madison Avenue, New York, NY 10029, USA,Present address: Department of Neuroscience, Icahn School of Medicine, Mount Sinai Hospital, New York, NY, USA
| | - Cian P. McCafferty
- Department of Anatomy and Neuroscience and APC Microbiome Institute, University College Cork, Cork, Ireland,Present address: Department of Neurology, Yale University School of Medicine, New Haven, CT, USA
| | - Javier A. Bravo
- Grupo de NeuroGastroBioquímica, Laboratorio e Química Biológica & Bioquímica de Sistemas, Instituto de Química, Facultad de Ciencias, Pontificia Universidad Católica de Valparaíso, Valparaíso, Chile
| | - Nicolas Singewald
- Department of Pharmacology and Toxicology, Institute of Pharmacy and Center for Molecular Biosciences Innsbruck (CMBI), University of Innsbruck, Innsbruck, Austria
| | - Andrew Holmes
- Laboratory of Behavioral and Genomic Neuroscience, National Institute on Alcohol Abuse and Alcoholism, Rockville, MD, USA
| | - John F. Cryan
- Department of Anatomy and Neuroscience and APC Microbiome Institute, University College Cork, Cork, Ireland
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13
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Bjerke IE, Øvsthus M, Andersson KA, Blixhavn CH, Kleven H, Yates SC, Puchades MA, Bjaalie JG, Leergaard TB. Navigating the Murine Brain: Toward Best Practices for Determining and Documenting Neuroanatomical Locations in Experimental Studies. Front Neuroanat 2018; 12:82. [PMID: 30450039 PMCID: PMC6224483 DOI: 10.3389/fnana.2018.00082] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2018] [Accepted: 09/19/2018] [Indexed: 12/24/2022] Open
Abstract
In experimental neuroscientific research, anatomical location is a key attribute of experimental observations and critical for interpretation of results, replication of findings, and comparison of data across studies. With steadily rising numbers of publications reporting basic experimental results, there is an increasing need for integration and synthesis of data. Since comparison of data relies on consistently defined anatomical locations, it is a major concern that practices and precision in the reporting of location of observations from different types of experimental studies seem to vary considerably. To elucidate and possibly meet this challenge, we have evaluated and compared current practices for interpreting and documenting the anatomical location of measurements acquired from murine brains with different experimental methods. Our observations show substantial differences in approach, interpretation and reproducibility of anatomical locations among reports of different categories of experimental research, and strongly indicate that ambiguous reports of anatomical location can be attributed to missing descriptions. Based on these findings, we suggest a set of minimum requirements for documentation of anatomical location in experimental murine brain research. We furthermore demonstrate how these requirements have been applied in the EU Human Brain Project to optimize workflows for integration of heterogeneous data in common reference atlases. We propose broad adoption of some straightforward steps for improving the precision of location metadata and thereby facilitating interpretation, reuse and integration of data.
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Affiliation(s)
- Ingvild E Bjerke
- Department of Molecular Medicine, Institute of Basic Medical Sciences, University of Oslo, Oslo, Norway
| | - Martin Øvsthus
- Department of Molecular Medicine, Institute of Basic Medical Sciences, University of Oslo, Oslo, Norway
| | - Krister A Andersson
- Department of Molecular Medicine, Institute of Basic Medical Sciences, University of Oslo, Oslo, Norway
| | - Camilla H Blixhavn
- Department of Molecular Medicine, Institute of Basic Medical Sciences, University of Oslo, Oslo, Norway
| | - Heidi Kleven
- Department of Molecular Medicine, Institute of Basic Medical Sciences, University of Oslo, Oslo, Norway
| | - Sharon C Yates
- Department of Molecular Medicine, Institute of Basic Medical Sciences, University of Oslo, Oslo, Norway
| | - Maja A Puchades
- Department of Molecular Medicine, Institute of Basic Medical Sciences, University of Oslo, Oslo, Norway
| | - Jan G Bjaalie
- Department of Molecular Medicine, Institute of Basic Medical Sciences, University of Oslo, Oslo, Norway
| | - Trygve B Leergaard
- Department of Molecular Medicine, Institute of Basic Medical Sciences, University of Oslo, Oslo, Norway
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14
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Fisher NM, Seto M, Lindsley CW, Niswender CM. Metabotropic Glutamate Receptor 7: A New Therapeutic Target in Neurodevelopmental Disorders. Front Mol Neurosci 2018; 11:387. [PMID: 30405350 PMCID: PMC6206046 DOI: 10.3389/fnmol.2018.00387] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2018] [Accepted: 10/01/2018] [Indexed: 12/27/2022] Open
Abstract
Neurodevelopmental disorders (NDDs) are characterized by a wide range of symptoms including delayed speech, intellectual disability, motor dysfunction, social deficits, breathing problems, structural abnormalities, and epilepsy. Unfortunately, current treatment strategies are limited and innovative new approaches are sorely needed to address these complex diseases. The metabotropic glutamate receptors are a class of G protein-coupled receptors that act to modulate neurotransmission across many brain structures. They have shown great promise as drug targets for numerous neurological and psychiatric diseases. Moreover, the development of subtype-selective allosteric modulators has allowed detailed studies of each receptor subtype. Here, we focus on the metabotropic glutamate receptor 7 (mGlu7) as a potential therapeutic target for NDDs. mGlu7 is expressed widely throughout the brain in regions that correspond to the symptom domains listed above and has established roles in synaptic physiology and behavior. Single nucleotide polymorphisms and mutations in the GRM7 gene have been associated with idiopathic autism and other NDDs in patients. In rodent models, existing literature suggests that decreased mGlu7 expression and/or function may lead to symptoms that overlap with those of NDDs. Furthermore, potentiation of mGlu7 activity has shown efficacy in a mouse model of Rett syndrome. In this review, we summarize current findings that provide rationale for the continued development of mGlu7 modulators as potential therapeutics.
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Affiliation(s)
- Nicole M Fisher
- Department of Pharmacology and Vanderbilt Center for Neuroscience Drug Discovery, Vanderbilt University, Nashville, TN, United States
| | - Mabel Seto
- Department of Pharmacology and Vanderbilt Center for Neuroscience Drug Discovery, Vanderbilt University, Nashville, TN, United States
| | - Craig W Lindsley
- Department of Pharmacology and Vanderbilt Center for Neuroscience Drug Discovery, Vanderbilt University, Nashville, TN, United States.,Department of Chemistry, Vanderbilt University, Nashville, TN, United States
| | - Colleen M Niswender
- Department of Pharmacology and Vanderbilt Center for Neuroscience Drug Discovery, Vanderbilt University, Nashville, TN, United States.,Vanderbilt Kennedy Center, Vanderbilt University Medical Center, Nashville, TN, United States
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15
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Ohno R, Miyagishi H, Tsuji M, Saito A, Miyagawa K, Kurokawa K, Takeda H. Yokukansan, a traditional Japanese herbal medicine, enhances the anxiolytic effect of fluvoxamine and reduces cortical 5-HT 2A receptor expression in mice. JOURNAL OF ETHNOPHARMACOLOGY 2018; 216:89-96. [PMID: 29382554 DOI: 10.1016/j.jep.2018.01.032] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/14/2017] [Revised: 01/26/2018] [Accepted: 01/26/2018] [Indexed: 06/07/2023]
Abstract
ETHNOPHARMACOLOGICAL RELEVANCE Yokukansan is a traditional Japanese herbal medicine that has been approved in Japan as a remedy for neurosis, insomnia, and irritability in children. It has also been reported to improve behavioral and psychological symptoms in patients with various forms of dementia. AIM OF THE STUDY To evaluate the usefulness of co-treatment with an antidepressant and an herbal medicine in the psychiatric field, the current study examined the effect of yokukansan on the anxiolytic-like effect of fluvoxamine in mice. MATERIALS AND METHODS The anxiolytic-like effect in mice was estimated by the contextual fear conditioning paradigm. Contextual fear conditioning consisted of two sessions, i.e., day 1 for the conditioning session and day 2 for the test session. The expression levels of 5-HT1A and 5-HT2A receptor in the mouse brain regions were quantified by western blot analysis. RESULTS A single administration of fluvoxamine (5-20 mg/kg, i.p.) before the test session dose-dependently and significantly suppressed freezing behavior in mice. In the combination study, a sub-effective dose of fluvoxamine (5 mg/kg, i.p.) significantly suppressed freezing behavior in mice that had been repeatedly pretreated with yokukansan (0.3 and 1 g/kg, p.o.) once a day for 6 days after the conditioning session. Western blot analysis revealed that the expression level of 5-HT2A receptor was specifically decreased in the prefrontal cortex of mice that had been administered yokukansan and fluvoxamine. Furthermore, microinjection of the 5-HT2A receptor antagonist ketanserin (5 nmol/mouse) into the prefrontal cortex significantly suppressed freezing behavior. CONCLUSION The present findings indicate that repeated treatment with yokukansan synergistically enhances the anxiolytic-like effect of fluvoxamine in the contextual fear conditioning paradigm in mice in conjunction with a decrease in 5-HT2A receptor-mediated signaling in the prefrontal cortex. Therefore, combination therapy with fluvoxamine and yokukansan may be beneficial for the treatment of anxiety disorders.
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MESH Headings
- Animals
- Anti-Anxiety Agents/pharmacology
- Anxiety/metabolism
- Anxiety/physiopathology
- Anxiety/prevention & control
- Anxiety/psychology
- Behavior, Animal/drug effects
- Conditioning, Psychological/drug effects
- Disease Models, Animal
- Dose-Response Relationship, Drug
- Drug Synergism
- Drug Therapy, Combination
- Drugs, Chinese Herbal/pharmacology
- Fear/drug effects
- Fluvoxamine/pharmacology
- Male
- Mice, Inbred ICR
- Motor Activity/drug effects
- Prefrontal Cortex/drug effects
- Prefrontal Cortex/metabolism
- Prefrontal Cortex/physiopathology
- Receptor, Serotonin, 5-HT2A/drug effects
- Receptor, Serotonin, 5-HT2A/metabolism
- Serotonin 5-HT2 Receptor Antagonists/pharmacology
- Signal Transduction/drug effects
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Affiliation(s)
- Rintaro Ohno
- Department of Pharmacology, School of Pharmacy, International University of Health and Welfare, 2600-1 Kitakanemaru, Ohtawara, Tochigi 324-8501, Japan
| | - Hiroko Miyagishi
- Department of Pharmacology, School of Pharmacy, International University of Health and Welfare, 2600-1 Kitakanemaru, Ohtawara, Tochigi 324-8501, Japan
| | - Minoru Tsuji
- Department of Pharmacology, School of Pharmacy, International University of Health and Welfare, 2600-1 Kitakanemaru, Ohtawara, Tochigi 324-8501, Japan.
| | - Atsumi Saito
- Department of Pharmacology, School of Pharmacy, International University of Health and Welfare, 2600-1 Kitakanemaru, Ohtawara, Tochigi 324-8501, Japan
| | - Kazuya Miyagawa
- Department of Pharmacology, School of Pharmacy, International University of Health and Welfare, 2600-1 Kitakanemaru, Ohtawara, Tochigi 324-8501, Japan
| | - Kazuhiro Kurokawa
- Department of Pharmacology, School of Pharmacy, International University of Health and Welfare, 2600-1 Kitakanemaru, Ohtawara, Tochigi 324-8501, Japan
| | - Hiroshi Takeda
- Department of Pharmacology, School of Pharmacy, International University of Health and Welfare, 2600-1 Kitakanemaru, Ohtawara, Tochigi 324-8501, Japan
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16
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Zussy C, Gómez-Santacana X, Rovira X, De Bundel D, Ferrazzo S, Bosch D, Asede D, Malhaire F, Acher F, Giraldo J, Valjent E, Ehrlich I, Ferraguti F, Pin JP, Llebaria A, Goudet C. Dynamic modulation of inflammatory pain-related affective and sensory symptoms by optical control of amygdala metabotropic glutamate receptor 4. Mol Psychiatry 2018; 23:509-520. [PMID: 27994221 DOI: 10.1038/mp.2016.223] [Citation(s) in RCA: 49] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/03/2016] [Revised: 10/06/2016] [Accepted: 10/14/2016] [Indexed: 12/30/2022]
Abstract
Contrary to acute pain, chronic pain does not serve as a warning signal and must be considered as a disease per se. This pathology presents a sensory and psychological dimension at the origin of affective and cognitive disorders. Being largely refractory to current pharmacotherapies, identification of endogenous systems involved in persistent and chronic pain is crucial. The amygdala is a key brain region linking pain sensation with negative emotions. Here, we show that activation of a specific intrinsic neuromodulatory system within the amygdala associated with type 4 metabotropic glutamate receptors (mGlu4) abolishes sensory and affective symptoms of persistent pain such as hypersensitivity to pain, anxiety- and depression-related behaviors, and fear extinction impairment. Interestingly, neuroanatomical and synaptic analysis of the amygdala circuitry suggests that the effects of mGlu4 activation occur outside the central nucleus via modulation of multisensory thalamic inputs to lateral amygdala principal neurons and dorso-medial intercalated cells. Furthermore, we developed optogluram, a small diffusible photoswitchable positive allosteric modulator of mGlu4. This ligand allows the control of endogenous mGlu4 activity with light. Using this photopharmacological approach, we rapidly and reversibly inhibited behavioral symptoms associated with persistent pain through optical control of optogluram in the amygdala of freely behaving animals. Altogether, our data identify amygdala mGlu4 signaling as a mechanism that bypasses central sensitization processes to dynamically modulate persistent pain symptoms. Our findings help to define novel and more precise therapeutic interventions for chronic pain, and exemplify the potential of optopharmacology to study the dynamic activity of endogenous neuromodulatory mechanisms in vivo.
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Affiliation(s)
- C Zussy
- Institut de Génomique Fonctionnelle, CNRS, UMR-5203, Université de Montpellier, Montpellier, France.,INSERM, U1191, Montpellier, France
| | - X Gómez-Santacana
- MCS, Laboratory of Medicinal Chemistry, Institute for Advanced Chemistry of Catalonia (IQAC-CSIC), Barcelona, Spain.,Laboratory of Molecular Neuropharmacology and Bioinformatics, Institut de Neurociències and Unitat de Bioestadística, Universitat Autònoma de Barcelona, Bellaterra, Spain
| | - X Rovira
- Institut de Génomique Fonctionnelle, CNRS, UMR-5203, Université de Montpellier, Montpellier, France.,INSERM, U1191, Montpellier, France
| | - D De Bundel
- Institut de Génomique Fonctionnelle, CNRS, UMR-5203, Université de Montpellier, Montpellier, France.,INSERM, U1191, Montpellier, France
| | - S Ferrazzo
- Department of Pharmacology, Innsbruck Medical University, Innsbruck, Austria
| | - D Bosch
- Hertie Institute for Clinical Brain Research, University of Tübingen, Tübingen, Germany.,Werner Reichardt Centre for Integrative Neuroscience, University of Tübingen, Tübingen, Germany
| | - D Asede
- Hertie Institute for Clinical Brain Research, University of Tübingen, Tübingen, Germany.,Werner Reichardt Centre for Integrative Neuroscience, University of Tübingen, Tübingen, Germany
| | - F Malhaire
- Institut de Génomique Fonctionnelle, CNRS, UMR-5203, Université de Montpellier, Montpellier, France.,INSERM, U1191, Montpellier, France
| | - F Acher
- Laboratoire de Chimie et Biochimie Pharmacologiques et Toxicologiques, CNRS UMR8601, Université Paris Descartes, Sorbonne Paris Cité, Paris, France
| | - J Giraldo
- Laboratory of Molecular Neuropharmacology and Bioinformatics, Institut de Neurociències and Unitat de Bioestadística, Universitat Autònoma de Barcelona, Bellaterra, Spain.,Network Biomedical Research Center on Mental Health (CIBERSAM), Madrid, Spain
| | - E Valjent
- Institut de Génomique Fonctionnelle, CNRS, UMR-5203, Université de Montpellier, Montpellier, France.,INSERM, U1191, Montpellier, France
| | - I Ehrlich
- Hertie Institute for Clinical Brain Research, University of Tübingen, Tübingen, Germany.,Werner Reichardt Centre for Integrative Neuroscience, University of Tübingen, Tübingen, Germany
| | - F Ferraguti
- Department of Pharmacology, Innsbruck Medical University, Innsbruck, Austria
| | - J-P Pin
- Institut de Génomique Fonctionnelle, CNRS, UMR-5203, Université de Montpellier, Montpellier, France.,INSERM, U1191, Montpellier, France
| | - A Llebaria
- MCS, Laboratory of Medicinal Chemistry, Institute for Advanced Chemistry of Catalonia (IQAC-CSIC), Barcelona, Spain
| | - C Goudet
- Institut de Génomique Fonctionnelle, CNRS, UMR-5203, Université de Montpellier, Montpellier, France.,INSERM, U1191, Montpellier, France
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17
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Differential Expression of Munc13-2 Produces Unique Synaptic Phenotypes in the Basolateral Amygdala of C57BL/6J and DBA/2J Mice. J Neurosci 2017; 36:10964-10977. [PMID: 27798178 DOI: 10.1523/jneurosci.1785-16.2016] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2016] [Accepted: 08/28/2016] [Indexed: 11/21/2022] Open
Abstract
C57BL/6J (B6) and DBA/2J (D2) mice are well known to differentially express a number of behavioral phenotypes, including anxiety-like behavior, fear conditioning, and drug self-administration. However, the cellular mechanisms contributing to these differences remain unclear. Given the basolateral amygdala (BLA) contributes to these behaviors, we characterized strain-dependent differences in presynaptic and postsynaptic function in BLA neurons by integrating electrophysiological, biochemical, and genetic approaches to identify specific molecular mechanisms. We found that D2 glutamatergic synapses expressed enhanced release probability and lower sensitivity to both the inhibitory effects of low extracellular calcium and facilitation by phorbol esters. Furthermore, repetitive stimulation of BLA afferents at low (2 Hz) or high (40 Hz) frequencies revealed that B6 terminals, relative to D2 terminals, were more sensitive to synaptic fatigue principally because of reduced vesicle recycling rates. Additionally, B6 synapses exhibited more robust augmentation of spontaneous release after repetitive stimulation relative to the D2 strain. In silico analysis of the inheritance of synaptic physiology from an array of BXD recombinant inbred strains (Jansen et al., 2011) identified a segment on chromosome 4 containing the gene encoding Munc13-2, which has calcium-/phorbol ester-binding domains and controls presynaptic function. We subsequently found that B6 mice express substantially higher levels of Munc13-2 compared with the D2 strain whereas expression of several release-related proteins, including Munc13-1, was equivalent. We then knocked down the expression of Munc13-2 in B6 mice using a short hairpin RNA and found this recapitulated the presynaptic phenotype of D2 BLA synapses. SIGNIFICANCE STATEMENT DBA/2J and C57BL/6J mice have been used to understand the genetic mechanisms controlling behaviors related to a number of psychiatric illnesses. However, the fundamental neurobiological mechanisms producing these behavioral characteristics remain unresolved. Here we identify a critical family of presynaptic proteins differentially expressed by these strains that control strain-dependent synaptic physiology. This family of proteins regulates excitation/secretion coupling, vesicle recycling, and short-term plasticity throughout the CNS. Thus, differential inheritance of proteins like Munc13-2 has broad implications for genetic control over a wide variety of pathological behaviors. Importantly, these proteins also contain a large number of modulatory sites, making them attractive potential targets for the development of novel neuropharmaceutical treatments.
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18
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Palazzo E, Marabese I, de Novellis V, Rossi F, Maione S. Metabotropic Glutamate Receptor 7: From Synaptic Function to Therapeutic Implications. Curr Neuropharmacol 2017; 14:504-13. [PMID: 27306064 PMCID: PMC4983754 DOI: 10.2174/1570159x13666150716165323] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2015] [Revised: 05/20/2015] [Accepted: 07/14/2015] [Indexed: 11/22/2022] Open
Abstract
Metabotropic glutamate receptor 7 (mGluR7) is localized presynaptically at the active zone of neurotransmitter release. Unlike mGluR4 and mGluR8, which share mGluR7's presynaptic location, mGluR7 shows low affinity for glutamate and is activated only by high glutamate concentrations. Its wide distribution in the central nervous system (CNS) and evolutionary conservation across species suggest that mGluR7 plays a primary role in controlling excitatory synapse function. High mGluR7 expression has been observed in several brain regions that are critical for CNS functioning and are involved in neurological and psychiatric disorder development. Until the recent discovery of selective ligands for mGluR7, techniques to elucidate its role in neural function were limited to the use of knockout mice and gene silencing. Studies using these two techniques have revealed that mGluR7 modulates emotionality, stress and fear responses. N,N`-dibenzhydrylethane-1,2-diamine dihydrochloride (AMN082) was reported as the first selective mGluR7 allosteric agonist. Pharmacological effects of AMN082 have not completely confirmed the mGluR7-knockout mouse phenotype; this has been attributed to rapid receptor internalization after drug treatment and to the drug's apparent lack of in vivo selectivity. Therefore, the more recently developed mGluR7 negative allosteric modulators (NAMs) are crucial for understanding mGluR7 function and for exploiting its potential as a target for therapeutic interventions. This review presents the main findings regarding mGluR7's effect on modulation of synaptic function and its role in normal CNS function and in models of neurologic and psychiatric disorders.
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Affiliation(s)
- Enza Palazzo
- Department of Anesthesiology, Surgery and Emergency, The Second University of Naples, Piazza Luigi Miraglia 2, 80138 Naples, Italy.
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19
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Selective agonism of mGlu8 receptors by (S)-3,4-dicarboxyphenylglycine does not affect sleep stages in the rat. Pharmacol Rep 2016; 69:97-104. [PMID: 27914294 DOI: 10.1016/j.pharep.2016.09.019] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2016] [Revised: 09/16/2016] [Accepted: 09/21/2016] [Indexed: 11/24/2022]
Abstract
BACKGROUND Metabotropic glutamate receptors (mGlu) play a role in a number of physiological processes and behaviors, as well as in certain pathological conditions and diseases. New drugs targetting mGlu receptors are being developed with treatment purposes. Recent data indicates that glutamate is involved in sleep, and pharmacological manipulation of distinct subtypes of mGlu receptors affect sleep. Here the consequences of selective pharmacological agonism of mGlu8 receptor upon sleep and wakefulness are explored for the first time. METHODS 32 male Wistar rats were stereotaxically prepared for polysomnography. (S)-3,4-dicarboxyphenylglycine (S)-3,4-DCPG (5, 10, and 20mg/kg, ip), a selective and potent mGlu8 receptor agonist, or physiological saline was administered one hour after the light period began. RESULTS Compared to control vehicle, (S)-3,4-DCPG, did not affect, at any of the doses given, the sleep and wakefulness parameters examined in the general analysis of the three hours of recording. Drug effects across time were studied analyzing three one-hour time blocks, control and experimental groups did not show any significant difference in the sleep and wakefulness parameters analyzed. Latency to sleep stages did not significantly vary between vehicle and treatment groups. CONCLUSIONS Results indicate that pharmacological activation of mGlu8 receptor by (S)-3,4-DCPG (5, 10, 20mg/kg, ip) does not affect sleep and wakefulness in the rat, suggesting that pharmacological agonism of these receptors may not influence sleep. Further research is needed to verify whether new drugs acting on these receptors lack of effect upon sleep and wakefulness.
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20
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Jaitner C, Reddy C, Abentung A, Whittle N, Rieder D, Delekate A, Korte M, Jain G, Fischer A, Sananbenesi F, Cera I, Singewald N, Dechant G, Apostolova G. Satb2 determines miRNA expression and long-term memory in the adult central nervous system. eLife 2016; 5. [PMID: 27897969 PMCID: PMC5207769 DOI: 10.7554/elife.17361] [Citation(s) in RCA: 56] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2016] [Accepted: 11/28/2016] [Indexed: 01/09/2023] Open
Abstract
SATB2 is a risk locus for schizophrenia and encodes a DNA-binding protein that regulates higher-order chromatin configuration. In the adult brain Satb2 is almost exclusively expressed in pyramidal neurons of two brain regions important for memory formation, the cerebral cortex and the CA1-hippocampal field. Here we show that Satb2 is required for key hippocampal functions since deletion of Satb2 from the adult mouse forebrain prevents the stabilization of synaptic long-term potentiation and markedly impairs long-term fear and object discrimination memory. At the molecular level, we find that synaptic activity and BDNF up-regulate Satb2, which itself binds to the promoters of coding and non-coding genes. Satb2 controls the hippocampal levels of a large cohort of miRNAs, many of which are implicated in synaptic plasticity and memory formation. Together, our findings demonstrate that Satb2 is critically involved in long-term plasticity processes in the adult forebrain that underlie the consolidation and stabilization of context-linked memory. DOI:http://dx.doi.org/10.7554/eLife.17361.001
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Affiliation(s)
- Clemens Jaitner
- Institute for Neuroscience, Medical University of Innsbruck, Innsbruck, Austria
| | - Chethan Reddy
- Institute for Neuroscience, Medical University of Innsbruck, Innsbruck, Austria
| | - Andreas Abentung
- Institute for Neuroscience, Medical University of Innsbruck, Innsbruck, Austria
| | - Nigel Whittle
- Department of Pharmacology and Toxicology, University of Innsbruck, Innsbruck, Austria
| | - Dietmar Rieder
- Division of Bioinformatics, Biocenter, Medical University of Innsbruck, Innsbruck, Austria
| | - Andrea Delekate
- Zoological Institute, Technical University Braunschweig, Braunschweig, Germany
| | - Martin Korte
- Zoological Institute, Technical University Braunschweig, Braunschweig, Germany.,AG Neuroinflammation and Neurodegeneration (NIND), Braunschweig, Germany
| | - Gaurav Jain
- Research Group for Epigenetics in Neurodegenerative Diseases, German Center for Neurodegenerative Diseases, Göttingen, Germany.,Research Group for Complex Neurodegenerative Disorders, German Center for Neurodegenerative Diseases, Göttingen, Germany
| | - Andre Fischer
- Research Group for Epigenetics in Neurodegenerative Diseases, German Center for Neurodegenerative Diseases, Göttingen, Germany.,Department of Psychiatry and Psychotherapy, University Medical Center, German Center for Neurodegenerative Diseases, Göttingen, Germany
| | - Farahnaz Sananbenesi
- Research Group for Complex Neurodegenerative Disorders, German Center for Neurodegenerative Diseases, Göttingen, Germany
| | - Isabella Cera
- Institute for Neuroscience, Medical University of Innsbruck, Innsbruck, Austria
| | - Nicolas Singewald
- Department of Pharmacology and Toxicology, University of Innsbruck, Innsbruck, Austria
| | - Georg Dechant
- Institute for Neuroscience, Medical University of Innsbruck, Innsbruck, Austria
| | - Galina Apostolova
- Institute for Neuroscience, Medical University of Innsbruck, Innsbruck, Austria
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21
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Krishnan B, Scott MT, Pollandt S, Schroeder B, Kurosky A, Shinnick-Gallagher P. Fear potentiated startle increases phospholipase D (PLD) expression/activity and PLD-linked metabotropic glutamate receptor mediated post-tetanic potentiation in rat amygdala. Neurobiol Learn Mem 2016; 128:65-79. [PMID: 26748024 PMCID: PMC4744522 DOI: 10.1016/j.nlm.2015.12.009] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2015] [Revised: 12/08/2015] [Accepted: 12/25/2015] [Indexed: 12/30/2022]
Abstract
Long-term memory (LTM) of fear stores activity dependent modifications that include changes in amygdala signaling. Previously, we identified an enhanced probability of release of glutamate mediated signaling to be important in rat fear potentiated startle (FPS), a well-established translational behavioral measure of fear. Here, we investigated short- and long-term synaptic plasticity in FPS involving metabotropic glutamate receptors (mGluRs) and associated downstream proteomic changes in the thalamic-lateral amygdala pathway (Th-LA). Aldolase A, an inhibitor of phospholipase D (PLD), expression was reduced, concurrent with significantly elevated PLD protein expression. Blocking the PLD-mGluR signaling significantly reduced PLD activity. While transmitter release probability increased in FPS, PLD-mGluR agonist and antagonist actions were occluded. In the unpaired group (UNP), blocking the PLD-mGluR increased while activating the receptor decreased transmitter release probability, consistent with decreased synaptic potentials during tetanic stimulation. FPS Post-tetanic potentiation (PTP) immediately following long-term potentiation (LTP) induction was significantly increased. Blocking PLD-mGluR signaling prevented PTP and reduced cumulative PTP probability but not LTP maintenance in both groups. These effects are similar to those mediated through mGluR7, which is co-immunoprecipitated with PLD in FPS. Lastly, blocking mGluR-PLD in the rat amygdala was sufficient to prevent behavioral expression of fear memory. Thus, our study in the Th-LA pathway provides the first evidence for PLD as an important target of mGluR signaling in amygdala fear-associated memory. Importantly, the PLD-mGluR provides a novel therapeutic target for treating maladaptive fear memories in posttraumatic stress and anxiety disorders.
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MESH Headings
- Amygdala/enzymology
- Amygdala/physiology
- Animals
- Conditioning, Classical/drug effects
- Conditioning, Classical/physiology
- Cyclopropanes/pharmacology
- Electric Stimulation
- Excitatory Postsynaptic Potentials/drug effects
- Fear/drug effects
- Fear/physiology
- Fructose-Bisphosphate Aldolase/metabolism
- Glycine/analogs & derivatives
- Glycine/pharmacology
- Long-Term Potentiation/drug effects
- Male
- Memory, Long-Term/drug effects
- Memory, Long-Term/physiology
- Neural Pathways/drug effects
- Neural Pathways/physiology
- Phospholipase D/antagonists & inhibitors
- Phospholipase D/metabolism
- Phospholipase D/physiology
- Rats
- Rats, Sprague-Dawley
- Receptors, Metabotropic Glutamate/agonists
- Receptors, Metabotropic Glutamate/antagonists & inhibitors
- Receptors, Metabotropic Glutamate/physiology
- Reflex, Startle/drug effects
- Reflex, Startle/physiology
- Thalamus/physiology
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Affiliation(s)
- Balaji Krishnan
- Department of Pharmacology & Toxicology, University of Texas Medical Branch, Galveston, TX, United States; UTMB Mitchell Center for Neurodegenerative Diseases, Department of Neurology, University of Texas Medical Branch, Galveston, TX, United States.
| | - Michael T Scott
- Department of Pharmacology & Toxicology, University of Texas Medical Branch, Galveston, TX, United States
| | - Sebastian Pollandt
- Department of Pharmacology & Toxicology, University of Texas Medical Branch, Galveston, TX, United States
| | - Bradley Schroeder
- Department of Pharmacology & Toxicology, University of Texas Medical Branch, Galveston, TX, United States
| | - Alexander Kurosky
- UTMB NHLBI Proteomics Center, Department of Biochemistry & Molecular Biology, University of Texas Medical Branch, Galveston, TX, United States
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22
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Peterlik D, Flor PJ, Uschold-Schmidt N. The Emerging Role of Metabotropic Glutamate Receptors in the Pathophysiology of Chronic Stress-Related Disorders. Curr Neuropharmacol 2016; 14:514-39. [PMID: 27296643 PMCID: PMC4983752 DOI: 10.2174/1570159x13666150515234920] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2015] [Revised: 04/04/2015] [Accepted: 05/12/2015] [Indexed: 12/28/2022] Open
Abstract
Chronic stress-related psychiatric conditions such as anxiety, depression, and alcohol abuse are an enormous public health concern. The etiology of these pathologies is complex, with psychosocial stressors being among the most frequently discussed risk factors. The brain glutamatergic neurotransmitter system has often been found involved in behaviors and pathophysiologies resulting from acute stress and fear. Despite this, relatively little is known about the role of glutamatergic system components in chronic psychosocial stress, neither in rodents nor in humans. Recently, drug discovery efforts at the metabotropic receptor subtypes of the glutamatergic system (mGlu1-8 receptors) led to the identification of pharmacological tools with emerging potential in psychiatric conditions. But again, the contribution of individual mGlu subtypes to the manifestation of physiological, molecular, and behavioral consequences of chronic psychosocial stress remains still largely unaddressed. The current review will describe animal models typically used to analyze acute and particularly chronic stress conditions, including models of psychosocial stress, and there we will discuss the emerging roles for mGlu receptor subtypes. Indeed, accumulating evidence indicates relevance and potential therapeutic usefulness of mGlu2/3 ligands and mGlu5 receptor antagonists in chronic stress-related disorders. In addition, a role for further mechanisms, e.g. mGlu7-selective compounds, is beginning to emerge. These mechanisms are important to be analyzed in chronic psychosocial stress paradigms, e.g. in the chronic subordinate colony housing (CSC) model. We summarize the early results and discuss necessary future investigations, especially for mGlu5 and mGlu7 receptor blockers, which might serve to suggest improved therapeutic strategies to treat stress-related disorders.
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Affiliation(s)
| | - Peter J Flor
- Faculty of Biology and Preclinical Medicine, University of Regensburg, D-93053 Regensburg, Germany.
| | - Nicole Uschold-Schmidt
- Faculty of Biology and Preclinical Medicine, University of Regensburg, D-93053 Regensburg, Germany.
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23
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Goddyn H, Callaerts-Vegh Z, D'Hooge R. Functional Dissociation of Group III Metabotropic Glutamate Receptors Revealed by Direct Comparison between the Behavioral Profiles of Knockout Mouse Lines. Int J Neuropsychopharmacol 2015; 18:pyv053. [PMID: 25999589 PMCID: PMC4756720 DOI: 10.1093/ijnp/pyv053] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/24/2015] [Accepted: 05/07/2015] [Indexed: 12/22/2022] Open
Abstract
BACKGROUND Group III metabotropic glutamate receptors (mGlu4, mGlu7, mGlu8) display differential brain distribution, which suggests different behavioral functions. However, comparison across the available animal studies remains methodologically hazardous and controversial. The present report directly compares knockouts for each group III receptor subtype using a single behavioral test battery and multivariate analysis. METHODS The behavioral phenotypes of C57BL/6J mice lacking mGlu4, mGlu7, or mGlu8 and their respective littermates were examined using a multimetric test battery, which included elements of neuromotor performance, exploratory behavior, and learning and memory. Multivariate statistical methods were used to identify subtype-specific behavioral profiles and variables that distinguished between these mouse lines. RESULTS It generally appears that mGlu7 plays a significant role in hippocampus-dependent spatial learning and in some fear-related behaviors, whereas mGlu4 is most clearly involved in startle and motivational processes. Excepting its influence on body weight, the effect of mGlu8 deletion on behavior appears more subtle than that of the other group III receptors. These receptors have been proposed as potential drug targets for a variety of psychopathological conditions. CONCLUSION On the basis of these controlled comparisons, we presently conclude that the different group III receptors indeed have quite distinct behavioral functions.
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Affiliation(s)
- Hannelore Goddyn
- KU Leuven, Laboratory of Biological Psychology, Leuven, Belgium (Drs Goddyn, Callaerts-Vegh, and D'Hooge)
| | - Zsuzsanna Callaerts-Vegh
- KU Leuven, Laboratory of Biological Psychology, Leuven, Belgium (Drs Goddyn, Callaerts-Vegh, and D'Hooge)
| | - Rudi D'Hooge
- KU Leuven, Laboratory of Biological Psychology, Leuven, Belgium (Drs Goddyn, Callaerts-Vegh, and D'Hooge).
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24
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Asede D, Bosch D, Lüthi A, Ferraguti F, Ehrlich I. Sensory inputs to intercalated cells provide fear-learning modulated inhibition to the basolateral amygdala. Neuron 2015; 86:541-54. [PMID: 25843406 DOI: 10.1016/j.neuron.2015.03.008] [Citation(s) in RCA: 69] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2014] [Revised: 01/07/2015] [Accepted: 02/25/2015] [Indexed: 12/16/2022]
Abstract
Increasing evidence suggests that parallel plastic processes in the amygdala involve inhibitory elements to control fear and extinction memory. GABAergic medial paracapsular intercalated cells (mpITCs) are thought to relay activity from basolateral nucleus (BLA) and prefrontal cortex to inhibit central amygdala output during suppression of fear. Recently, projection diversity and differential behavioral activation of mpITCs in distinct fear states suggest additional functions. Here, we show that mpITCs receive convergent sensory thalamic and cortical inputs that undergo fear learning-related changes and are dynamically modulated via presynaptic GABAB receptors recruited by GABA released from the mpITC network. Among mpITCs, we identify cells that inhibit but are also mutually activated by BLA principal neurons. Thus, mpITCs take part in fear learning-modulated feedforward and feedback inhibitory circuits to simultaneously control amygdala input and output nuclei. Our findings place mpITCs in a unique position to gate acquired amygdala-dependent behaviors via their direct sensory inputs.
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Affiliation(s)
- Douglas Asede
- Hertie Institute for Clinical Brain Research, University of Tübingen, Otfried-Müller-Straße 25, 72076 Tübingen, Germany; Werner Reichardt Centre for Integrative Neuroscience, University of Tübingen, Otfried-Müller-Straße 25, 72076 Tübingen, Germany; Graduate School of Neural and Behavioral Sciences, International Max Planck Research School, University of Tübingen, Österbergstrasse 3, 72074 Tübingen, Germany
| | - Daniel Bosch
- Hertie Institute for Clinical Brain Research, University of Tübingen, Otfried-Müller-Straße 25, 72076 Tübingen, Germany; Werner Reichardt Centre for Integrative Neuroscience, University of Tübingen, Otfried-Müller-Straße 25, 72076 Tübingen, Germany
| | - Andreas Lüthi
- Friedrich Miescher Institute for Biomedical Research, Maulbeerstrasse 66, 4058 Basel, Switzerland
| | - Francesco Ferraguti
- Department of Pharmacology, Innsbruck Medical University, Peter Mayr Straße 1a, 6020 Innsbruck, Austria
| | - Ingrid Ehrlich
- Hertie Institute for Clinical Brain Research, University of Tübingen, Otfried-Müller-Straße 25, 72076 Tübingen, Germany; Werner Reichardt Centre for Integrative Neuroscience, University of Tübingen, Otfried-Müller-Straße 25, 72076 Tübingen, Germany.
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25
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Bienvenu TCM, Busti D, Micklem BR, Mansouri M, Magill PJ, Ferraguti F, Capogna M. Large intercalated neurons of amygdala relay noxious sensory information. J Neurosci 2015; 35:2044-57. [PMID: 25653362 PMCID: PMC4315833 DOI: 10.1523/jneurosci.1323-14.2015] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2014] [Revised: 11/07/2014] [Accepted: 11/13/2014] [Indexed: 01/03/2023] Open
Abstract
Various GABAergic neuron types of the amygdala cooperate to control principal cell firing during fear-related and other behaviors, and understanding their specialized roles is important. Among GABAergic neurons, the so-called intercalated cells (ITCcs) are critically involved in the expression and extinction of fear memory. Tightly clustered small-sized spiny neurons constitute the majority of ITCcs, but they are surrounded by sparse, larger neurons (L-ITCcs) for which very little information is known. We report here a detailed neurochemical, structural and physiological characterization of rat L-ITCcs, as identified with juxtacellular recording/labeling in vivo. We supplement these data with anatomical and neurochemical analyses of nonrecorded L-ITCcs. We demonstrate that L-ITCcs are GABAergic, and strongly express metabotropic glutamate receptor 1α and GABAA receptor α1 subunit, together with moderate levels of parvalbumin. Furthermore, L-ITCcs are innervated by fibers enriched with metabotropic glutamate receptors 7a and/or 8a. In contrast to small-sized spiny ITCcs, L-ITCcs possess thick, aspiny dendrites, have highly branched, long-range axonal projections, and innervate interneurons in the basolateral amygdaloid complex. The axons of L-ITCcs also project to distant brain areas, such as the perirhinal, entorhinal, and endopiriform cortices. In vivo recorded L-ITCcs are strongly activated by noxious stimuli, such as hindpaw pinches or electrical footshocks. Consistent with this, we observed synaptic contacts on L-ITCc dendrites from nociceptive intralaminar thalamic nuclei. We propose that, during salient sensory stimulation, L-ITCcs disinhibit local and distant principal neurons, acting as "hub cells," to orchestrate the activity of a distributed network.
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Affiliation(s)
- Thomas C M Bienvenu
- Medical Research Council Anatomical Neuropharmacology Unit, Department of Pharmacology, University of Oxford, Oxford OX1 3TH, United Kingdom, and
| | - Daniela Busti
- Department of Pharmacology, Medical University of Innsbruck, 6020 Innsbruck, Austria
| | - Benjamin R Micklem
- Medical Research Council Anatomical Neuropharmacology Unit, Department of Pharmacology, University of Oxford, Oxford OX1 3TH, United Kingdom, and
| | - Mahnaz Mansouri
- Department of Pharmacology, Medical University of Innsbruck, 6020 Innsbruck, Austria
| | - Peter J Magill
- Medical Research Council Anatomical Neuropharmacology Unit, Department of Pharmacology, University of Oxford, Oxford OX1 3TH, United Kingdom, and
| | - Francesco Ferraguti
- Department of Pharmacology, Medical University of Innsbruck, 6020 Innsbruck, Austria
| | - Marco Capogna
- Medical Research Council Anatomical Neuropharmacology Unit, Department of Pharmacology, University of Oxford, Oxford OX1 3TH, United Kingdom, and
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26
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Therapeutic potential of group III metabotropic glutamate receptor ligands in pain. Curr Opin Pharmacol 2015; 20:64-72. [DOI: 10.1016/j.coph.2014.11.007] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2014] [Revised: 11/18/2014] [Accepted: 11/21/2014] [Indexed: 11/22/2022]
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27
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Singewald N, Schmuckermair C, Whittle N, Holmes A, Ressler KJ. Pharmacology of cognitive enhancers for exposure-based therapy of fear, anxiety and trauma-related disorders. Pharmacol Ther 2014; 149:150-90. [PMID: 25550231 PMCID: PMC4380664 DOI: 10.1016/j.pharmthera.2014.12.004] [Citation(s) in RCA: 273] [Impact Index Per Article: 27.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2014] [Accepted: 12/24/2014] [Indexed: 12/20/2022]
Abstract
Pathological fear and anxiety are highly debilitating and, despite considerable advances in psychotherapy and pharmacotherapy they remain insufficiently treated in many patients with PTSD, phobias, panic and other anxiety disorders. Increasing preclinical and clinical evidence indicates that pharmacological treatments including cognitive enhancers, when given as adjuncts to psychotherapeutic approaches [cognitive behavioral therapy including extinction-based exposure therapy] enhance treatment efficacy, while using anxiolytics such as benzodiazepines as adjuncts can undermine long-term treatment success. The purpose of this review is to outline the literature showing how pharmacological interventions targeting neurotransmitter systems including serotonin, dopamine, noradrenaline, histamine, glutamate, GABA, cannabinoids, neuropeptides (oxytocin, neuropeptides Y and S, opioids) and other targets (neurotrophins BDNF and FGF2, glucocorticoids, L-type-calcium channels, epigenetic modifications) as well as their downstream signaling pathways, can augment fear extinction and strengthen extinction memory persistently in preclinical models. Particularly promising approaches are discussed in regard to their effects on specific aspects of fear extinction namely, acquisition, consolidation and retrieval, including long-term protection from return of fear (relapse) phenomena like spontaneous recovery, reinstatement and renewal of fear. We also highlight the promising translational value of the preclinial research and the clinical potential of targeting certain neurochemical systems with, for example d-cycloserine, yohimbine, cortisol, and L-DOPA. The current body of research reveals important new insights into the neurobiology and neurochemistry of fear extinction and holds significant promise for pharmacologically-augmented psychotherapy as an improved approach to treat trauma and anxiety-related disorders in a more efficient and persistent way promoting enhanced symptom remission and recovery.
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Affiliation(s)
- N Singewald
- Department of Pharmacology and Toxicology, Institute of Pharmacy and CMBI, Leopold-Franzens University of Innsbruck, Innrain 80-82, A-6020 Innsbruck, Austria.
| | - C Schmuckermair
- Department of Pharmacology and Toxicology, Institute of Pharmacy and CMBI, Leopold-Franzens University of Innsbruck, Innrain 80-82, A-6020 Innsbruck, Austria
| | - N Whittle
- Department of Pharmacology and Toxicology, Institute of Pharmacy and CMBI, Leopold-Franzens University of Innsbruck, Innrain 80-82, A-6020 Innsbruck, Austria
| | - A Holmes
- Laboratory of Behavioral and Genomic Neuroscience, National Institute on Alcohol Abuse and Alcoholism, NIH, Bethesda, MD, USA
| | - K J Ressler
- Department of Psychiatry and Behavioral Sciences, Emory University School of Medicine, Atlanta, GA, USA
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28
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Bukalo O, Pinard CR, Holmes A. Mechanisms to medicines: elucidating neural and molecular substrates of fear extinction to identify novel treatments for anxiety disorders. Br J Pharmacol 2014; 171:4690-718. [PMID: 24835117 DOI: 10.1111/bph.12779] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2014] [Revised: 04/28/2014] [Accepted: 05/04/2014] [Indexed: 12/11/2022] Open
Abstract
The burden of anxiety disorders is growing, but the efficacy of available anxiolytic treatments remains inadequate. Cognitive behavioural therapy for anxiety disorders focuses on identifying and modifying maladaptive patterns of thinking and behaving, and has a testable analogue in rodents in the form of fear extinction. A large preclinical literature has amassed in recent years describing the neural and molecular basis of fear extinction in rodents. In this review, we discuss how this work is being harnessed to foster translational research on anxiety disorders and facilitate the search for new anxiolytic treatments. We begin by summarizing the anatomical and functional connectivity of a medial prefrontal cortex (mPFC)-amygdala circuit that subserves fear extinction, including new insights from optogenetics. We then cover some of the approaches that have been taken to model impaired fear extinction and associated impairments with mPFC-amygdala dysfunction. The principal goal of the review is to evaluate evidence that various neurotransmitter and neuromodulator systems mediate fear extinction by modulating the mPFC-amygdala circuitry. To that end, we describe studies that have tested how fear extinction is impaired or facilitated by pharmacological manipulations of dopamine, noradrenaline, 5-HT, GABA, glutamate, neuropeptides, endocannabinoids and various other systems, which either directly target the mPFC-amygdala circuit, or produce behavioural effects that are coincident with functional changes in the circuit. We conclude that there are good grounds to be optimistic that the progress in defining the molecular substrates of mPFC-amygdala circuit function can be effectively leveraged to identify plausible candidates for extinction-promoting therapies for anxiety disorders.
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Affiliation(s)
- Olena Bukalo
- Laboratory of Behavioral and Genomic Neuroscience, National Institute on Alcohol Abuse and Alcoholism, Bethesda, MD, USA
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29
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Mátyás F, Lee J, Shin HS, Acsády L. The fear circuit of the mouse forebrain: connections between the mediodorsal thalamus, frontal cortices and basolateral amygdala. Eur J Neurosci 2014; 39:1810-23. [DOI: 10.1111/ejn.12610] [Citation(s) in RCA: 76] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2014] [Revised: 03/31/2014] [Accepted: 04/03/2014] [Indexed: 11/27/2022]
Affiliation(s)
- Ferenc Mátyás
- Laboratory of Thalamus Research; Institute of Experimental Medicine; Hungarian Academy of Sciences; Szigony u 43 Budapest H-1083 Hungary
| | - JoonHyuk Lee
- Center for Cognition and Sociality; Institute for Basic Science (IBS); Daejeon Korea
- Department of Bio and Brain Engineering; Korea Advanced Institute of Science and Technology (KAIST); Daejeon Korea
| | - Hee-Sup Shin
- Center for Cognition and Sociality; Institute for Basic Science (IBS); Daejeon Korea
- Department of Bio and Brain Engineering; Korea Advanced Institute of Science and Technology (KAIST); Daejeon Korea
| | - László Acsády
- Laboratory of Thalamus Research; Institute of Experimental Medicine; Hungarian Academy of Sciences; Szigony u 43 Budapest H-1083 Hungary
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30
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Gee CE, Peterlik D, Neuhäuser C, Bouhelal R, Kaupmann K, Laue G, Uschold-Schmidt N, Feuerbach D, Zimmermann K, Ofner S, Cryan JF, van der Putten H, Fendt M, Vranesic I, Glatthar R, Flor PJ. Blocking metabotropic glutamate receptor subtype 7 (mGlu7) via the Venus flytrap domain (VFTD) inhibits amygdala plasticity, stress, and anxiety-related behavior. J Biol Chem 2014; 289:10975-10987. [PMID: 24596089 DOI: 10.1074/jbc.m113.542654] [Citation(s) in RCA: 58] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The metabotropic glutamate receptor subtype 7 (mGlu7) is an important presynaptic regulator of neurotransmission in the mammalian CNS. mGlu7 function has been linked to autism, drug abuse, anxiety, and depression. Despite this, it has been difficult to develop specific blockers of native mGlu7 signaling in relevant brain areas such as amygdala and limbic cortex. Here, we present the mGlu7-selective antagonist 7-hydroxy-3-(4-iodophenoxy)-4H-chromen-4-one (XAP044), which inhibits lateral amygdala long term potentiation (LTP) in brain slices from wild type mice with a half-maximal blockade at 88 nm. There was no effect of XAP044 on LTP of mGlu7-deficient mice, indicating that this pharmacological effect is mGlu7-dependent. Unexpectedly and in contrast to all previous mGlu7-selective drugs, XAP044 does not act via the seven-transmembrane region but rather via a binding pocket localized in mGlu7's extracellular Venus flytrap domain, a region generally known for orthosteric agonist binding. This was shown by chimeric receptor studies in recombinant cell line assays. XAP044 demonstrates good brain exposure and wide spectrum anti-stress and antidepressant- and anxiolytic-like efficacy in rodent behavioral paradigms. XAP044 reduces freezing during acquisition of Pavlovian fear and reduces innate anxiety, which is consistent with the phenotypes of mGlu7-deficient mice, the results of mGlu7 siRNA knockdown studies, and the inhibition of amygdala LTP by XAP044. Thus, we present an mGlu7 antagonist with a novel molecular mode of pharmacological action, providing significant application potential in psychiatry. Modeling the selective interaction between XAP044 and mGlu7's Venus flytrap domain, whose three-dimensional structure is already known, will facilitate future drug development supported by computer-assisted drug design.
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Affiliation(s)
- Christine E Gee
- Novartis Institutes for BioMedical Research, Novartis AG, CH-4057 Basel, Switzerland,; Center for Molecular Neurobiology Hamburg, University Medical Center Hamburg-Eppendorf, D-20249 Hamburg, Germany
| | - Daniel Peterlik
- Faculty of Biology and Preclinical Medicine, Laboratory of Molecular and Cellular Neurobiology, University of Regensburg, D-93053 Regensburg, Germany
| | - Christoph Neuhäuser
- Faculty of Biology and Preclinical Medicine, Laboratory of Molecular and Cellular Neurobiology, University of Regensburg, D-93053 Regensburg, Germany
| | - Rochdi Bouhelal
- Novartis Institutes for BioMedical Research, Novartis AG, CH-4057 Basel, Switzerland
| | - Klemens Kaupmann
- Novartis Institutes for BioMedical Research, Novartis AG, CH-4057 Basel, Switzerland
| | - Grit Laue
- Novartis Institutes for BioMedical Research, Novartis AG, CH-4057 Basel, Switzerland
| | - Nicole Uschold-Schmidt
- Faculty of Biology and Preclinical Medicine, Laboratory of Molecular and Cellular Neurobiology, University of Regensburg, D-93053 Regensburg, Germany
| | - Dominik Feuerbach
- Novartis Institutes for BioMedical Research, Novartis AG, CH-4057 Basel, Switzerland
| | - Kaspar Zimmermann
- Novartis Institutes for BioMedical Research, Novartis AG, CH-4057 Basel, Switzerland
| | - Silvio Ofner
- Novartis Institutes for BioMedical Research, Novartis AG, CH-4057 Basel, Switzerland
| | - John F Cryan
- Novartis Institutes for BioMedical Research, Novartis AG, CH-4057 Basel, Switzerland,; Department of Anatomy and Neuroscience, University of Cork, Cork, Ireland, and
| | - Herman van der Putten
- Novartis Institutes for BioMedical Research, Novartis AG, CH-4057 Basel, Switzerland
| | - Markus Fendt
- Novartis Institutes for BioMedical Research, Novartis AG, CH-4057 Basel, Switzerland,; Institute of Pharmacology and Toxicology and Center of Behavioral Brain Sciences, University of Magdeburg, D-39120 Magdeburg, Germany
| | - Ivo Vranesic
- Novartis Institutes for BioMedical Research, Novartis AG, CH-4057 Basel, Switzerland
| | - Ralf Glatthar
- Novartis Institutes for BioMedical Research, Novartis AG, CH-4057 Basel, Switzerland,.
| | - Peter J Flor
- Novartis Institutes for BioMedical Research, Novartis AG, CH-4057 Basel, Switzerland,; Faculty of Biology and Preclinical Medicine, Laboratory of Molecular and Cellular Neurobiology, University of Regensburg, D-93053 Regensburg, Germany,.
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31
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Palazzo E, Marabese I, Luongo L, Boccella S, Bellini G, Giordano ME, Rossi F, Scafuro M, Novellis VD, Maione S. Effects of a metabotropic glutamate receptor subtype 7 negative allosteric modulator in the periaqueductal grey on pain responses and rostral ventromedial medulla cell activity in rat. Mol Pain 2013; 9:44. [PMID: 24004843 PMCID: PMC3846361 DOI: 10.1186/1744-8069-9-44] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2013] [Accepted: 08/22/2013] [Indexed: 01/05/2023] Open
Abstract
The metabotropic glutamate receptor 7 (mGluR7) negative allosteric modulator, 6-(4-methoxyphenyl)-5-methyl-3-pyridin-4-ylisoxazolo[4,5-c]pyridin-4(5H)-one (MMPIP), was locally microinjected into the ventrolateral periaqueductal gray (VL PAG) and the effect on pain responses in formalin and spare nerve injury (SNI) -induced neuropathic pain models was monitored in the rat. The activity of rostral ventromedial medulla (RVM) “pronociceptive” ON and “antinociceptive” OFF cells was also evaluated. Intra–VL PAG MMPIP blocked the first and second phase of nocifensive behaviour in the formalin pain model. MMPIP increased the tail flick latency and simultaneously increased the activity of the OFF cells while inhibiting that of ON cells in rats with SNI of the sciatic nerve. MMPIP failed to modify nociceptive responses and associated RVM ON and OFF cell activity in sham rats. An increase in mGluR7 gene, protein and staining, the latter being associated with vesicular glutamate transporter-positive profiles, has been found in the VL PAG in SNI rats. Blockade of mGluR7 within the VL PAG has an antinociceptive effect in formalin and neuropathic pain models. VL PAG mGluR7 blockade offers a target for dis-inhibiting the VL PAG-RVM pathway and silencing pain in inflammatory and neuropathic pain models.
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Affiliation(s)
- Enza Palazzo
- Department of Anaesthesiology, Surgery and Emergency, The Second University of Naples, Piazza Luigi Miraglia 2, Naples 80178, Italy.
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Fendt M, Imobersteg S, Peterlik D, Chaperon F, Mattes C, Wittmann C, Olpe HR, Mosbacher J, Vranesic I, van der Putten H, McAllister KH, Flor PJ, Gee CE. Differential roles of mGlu(7) and mGlu(8) in amygdala-dependent behavior and physiology. Neuropharmacology 2013; 72:215-23. [PMID: 23664812 DOI: 10.1016/j.neuropharm.2013.04.052] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2013] [Revised: 04/09/2013] [Accepted: 04/18/2013] [Indexed: 11/26/2022]
Abstract
Glutamate transmission and synaptic plasticity in the amygdala are essential for the learning and expression of conditioned fear. Glutamate activates both ionotropic glutamate receptors and eight subtypes of metabotropic glutamate receptors (mGlu1-8). In the present study, we investigated the roles of mGlu7 and mGlu8 in amygdala-dependent behavior and synaptic plasticity. We show that ablation of mGlu7 but not mGlu8 attenuates long-term potentiation (LTP) at thalamo-lateral amygdala (LA) synapses where a strong association between LTP and learning has been demonstrated. mGlu7-deficient mice express a general deficit in conditioned fear whereas mGlu8-deficient mice show a dramatic reduction in contextual fear. The mGlu7 agonist AMN082 reduced thalamo-LA LTP and intra-amygdala administration blocked conditioned fear learning. In contrast, the mGlu8 agonist DCPG decreased synaptic transmission but not LTP at thalamo-LA synapses. Intra-amygdala DCPG selectively reduced the expression of contextual fear but did not affect the acquisition and expression of cued fear. Taken together, these data revealed very different roles for mGlu7 and mGlu8 in amygdala synaptic transmission, fear learning and its expression. These receptors seem promising targets for treating anxiety disorders with different underlying pathologies with exaggerated fear learning (mGlu7) or contextual fear (mGlu8).
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Affiliation(s)
- Markus Fendt
- Novartis Institutes for BioMedical Research, Neuroscience DA, Forum 1, Novartis Campus, CH-4056 Basel, Switzerland.
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Stafford JM, Maughan DK, Ilioi EC, Lattal KM. Exposure to a fearful context during periods of memory plasticity impairs extinction via hyperactivation of frontal-amygdalar circuits. Learn Mem 2013; 20:156-63. [PMID: 23422280 PMCID: PMC3578276 DOI: 10.1101/lm.029801.112] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2012] [Accepted: 12/20/2012] [Indexed: 11/25/2022]
Abstract
An issue of increasing theoretical and translational importance is to understand the conditions under which learned fear can be suppressed, or even eliminated. Basic research has pointed to extinction, in which an organism is exposed to a fearful stimulus (such as a context) in the absence of an expected aversive outcome (such as a shock). This extinction process results in the suppression of fear responses, but is generally thought to leave the original fearful memory intact. Here, we investigate the effects of extinction during periods of memory lability on behavioral responses and on expression of the immediate-early gene c-Fos within fear conditioning and extinction circuits. Our results show that long-term extinction is impaired when it occurs during time periods during which the memory should be most vulnerable to disruption (soon after conditioning or retrieval). These behavioral effects are correlated with hyperactivation of medial prefrontal cortex and amygdala subregions associated with fear expression rather than fear extinction. These findings demonstrate that behavioral experiences during periods of heightened fear prevent extinction and prolong the conditioned fear response.
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Affiliation(s)
| | | | | | - K. Matthew Lattal
- Department of Behavioral Neuroscience, Oregon Health & Science University, Portland, Oregon 97239-3098, USA
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