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Yoneda T, Kameyama K, Gotou T, Terata K, Takagi M, Yoshimura Y, Sakimura K, Kano M, Hata Y. Layer specific regulation of critical period timing and maturation of mouse visual cortex by endocannabinoids. iScience 2024; 27:110145. [PMID: 38952682 PMCID: PMC11215304 DOI: 10.1016/j.isci.2024.110145] [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: 05/25/2023] [Revised: 04/15/2024] [Accepted: 05/27/2024] [Indexed: 07/03/2024] Open
Abstract
Plasticity during the critical period is important for the functional maturation of cortical neurons. While characteristics of plasticity are diverse among cortical layers, it is unknown whether critical period timing is controlled by a common or unique molecular mechanism among them. We here clarified layer-specific regulation of the critical period timing of ocular dominance plasticity in the primary visual cortex. Mice lacking the endocannabinoid synthesis enzyme diacylglycerol lipase-α exhibited precocious critical period timing, earlier maturation of inhibitory synaptic function in layers 2/3 and 4, and impaired development of the binocular matching of orientation selectivity exclusively in layer 2/3. Activation of cannabinoid receptor restored ocular dominance plasticity at the normal critical period in layer 2/3. Suppression of GABAA receptor rescued precocious ocular dominance plasticity in layer 4. Therefore, endocannabinoids regulate critical period timing and maturation of visual function partly through the development of inhibitory synaptic functions in a layer-dependent manner.
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Affiliation(s)
- Taisuke Yoneda
- Division of Neuroscience, School of Life Science, Faculty of Medicine, Tottori University, Yonago 683-8503, Japan
- Division of Visual Information Processing, National Institute for Physiological Sciences, Okazaki 444-8585, Japan
- Graduate Institute for Advanced Studies, SOKENDAI, Okazaki 444-8585, Japan
| | - Katsuro Kameyama
- Division of Neuroscience, School of Life Science, Faculty of Medicine, Tottori University, Yonago 683-8503, Japan
| | - Takahiro Gotou
- Division of Neuroscience, School of Life Science, Faculty of Medicine, Tottori University, Yonago 683-8503, Japan
| | - Keiko Terata
- Division of Neuroscience, School of Life Science, Faculty of Medicine, Tottori University, Yonago 683-8503, Japan
| | - Masahiro Takagi
- Division of Visual Information Processing, National Institute for Physiological Sciences, Okazaki 444-8585, Japan
| | - Yumiko Yoshimura
- Division of Visual Information Processing, National Institute for Physiological Sciences, Okazaki 444-8585, Japan
- Graduate Institute for Advanced Studies, SOKENDAI, Okazaki 444-8585, Japan
| | - Kenji Sakimura
- Department of Animal Model Development, Brain Research Institute, Niigata University, Niigata 951-8585, Japan
| | - Masanobu Kano
- Department of Neurophysiology, Graduate School of Medicine, The University of Tokyo, Tokyo 113-0033, Japan
- International Research Center for Neurointelligence (WPI-IRCN), The University of Tokyo, Tokyo 113-0033, Japan
- Advanced Comprehensive Research Organization (ACRO), Teikyo University, Tokyo 173-0003, Japan
| | - Yoshio Hata
- Division of Neuroscience, School of Life Science, Faculty of Medicine, Tottori University, Yonago 683-8503, Japan
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Molina-Holgado E, Paniagua-Torija B, Arevalo-Martin A, Moreno-Luna R, Esteban PF, Le MQU, Del Cerro MDM, Garcia-Ovejero D. Cannabinoid Receptor 1 associates to different molecular complexes during GABAergic neuron maturation. J Neurochem 2021; 158:640-656. [PMID: 33942314 DOI: 10.1111/jnc.15381] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2021] [Revised: 04/13/2021] [Accepted: 04/29/2021] [Indexed: 01/08/2023]
Abstract
CB1 cannabinoid receptor is widely expressed in the central nervous system of animals from late prenatal development to adulthood. Appropriate activation and signaling of CB1 cannabinoid receptors in cortical interneurons are crucial during perinatal/postnatal ages and adolescence, when long-lasting changes in brain activity may elicit subsequent appearance of disorders in the adult brain. Here we used an optimized immunoprecipitation protocol based on specific antibodies followed by shot-gun proteomics to find CB1 interacting partners in postnatal rat GABAergic cortical neurons in vitro at two different stages of maturation. Besides describing new proteins associated with CB1 like dihydrolipoyllysine-residue acetyltransferase component of pyruvate dehydrogenase complex (DLAT), fatty acid synthase (FASN), tyrosine 3-monooxygenase/tryptophan 5-monooxygenase activation protein zeta (YWHAZ), voltage-dependent anion channel 1 (VDAC1), myosin phosphatase Rho-interacting protein (MPRIP) or usher syndrome type-1C protein-binding protein 1 (USHBP1), we show that the signaling complex of CB1 is different between maturational stages. Interestingly, the CB1 signaling complex is enriched at the more immature stage in mitochondrial associated proteins and metabolic molecular functions, whereas at more mature stage, CB1 complex is increased in maturation and synaptic-associated proteins. We describe also interacting partners specifically immunoprecipitated with either N-terminal or C-terminal CB1 directed antibodies. Our results highlight new players that may be affected by altered cannabinoid signaling at this critical window of postnatal cortical development.
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Affiliation(s)
- Eduardo Molina-Holgado
- Laboratory of Neuroinflammation, Hospital Nacional de Paraplejicos (SESCAM), Toledo, Spain
| | | | - Angel Arevalo-Martin
- Laboratory of Neuroinflammation, Hospital Nacional de Paraplejicos (SESCAM), Toledo, Spain
| | - Rafael Moreno-Luna
- Laboratory of Neuroinflammation, Hospital Nacional de Paraplejicos (SESCAM), Toledo, Spain
| | - Pedro F Esteban
- Laboratory of Neuroinflammation, Hospital Nacional de Paraplejicos (SESCAM), Toledo, Spain
| | - Minh Quynh Uyen Le
- Laboratory of Neuroinflammation, Hospital Nacional de Paraplejicos (SESCAM), Toledo, Spain
| | | | - Daniel Garcia-Ovejero
- Laboratory of Neuroinflammation, Hospital Nacional de Paraplejicos (SESCAM), Toledo, Spain
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Durieux LJA, Gilissen SRJ, Arckens L. Endocannabinoids and cortical plasticity: CB1R as a possible regulator of the excitation/inhibition balance in health and disease. Eur J Neurosci 2021; 55:971-988. [PMID: 33427341 DOI: 10.1111/ejn.15110] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2020] [Revised: 01/04/2021] [Accepted: 01/06/2021] [Indexed: 12/27/2022]
Abstract
The endocannabinoid system has been linked to neurological disorders in which the excitation inhibition (E/I) balance in the neocortex is dysregulated, such as schizophrenia. The main endocannabinoid receptor type 1 of the central nervous system-CB1R-is expressed on different cell types, that when activated, modulate the cortical E/I balance. Here we review how CB1R signalling contributes to phases of heightened plasticity of the neocortex. We review the major role of the CB1R in cortical plasticity throughout life, including the early life sensory critical periods, the later maturation phase of the association cortex in adolescence, and the adult phase of sensory deprivation-induced cortical plasticity. Endocannabinoid-mediated long-term potentiation and depression of synapse strength fine-tune the E/I balance in visual, somatosensory and association areas. We emphasize how a distinct set of key endocannabinoid-regulated elements such as GABA and glutamate release, basket parvalbumin interneurons, somatostatin interneurons and astrocytes, are essential for normal cortical plasticity and dysregulated in schizophrenia. Even though a lot of data has been gathered, mechanistic knowledge about the exact CB1R-based modulation of excitation and/or inhibition is still lacking depending on cortical area and maturation phase in life. We emphasize the importance of creating such detailed knowledge for a better comprehension of what underlies the dysregulation of the neocortex in schizophrenic patients in adulthood. We propose that taking age, brain area and cell type into consideration when modulating the cortical E/I imbalance via cannabinoid-based pharmacology may pave the way for better patient care.
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Affiliation(s)
- Lucas J A Durieux
- KU Leuven, Department of Biology, Laboratory of Neuroplasticity and Neuroproteomics, Leuven, Belgium.,Leuven Brain Institute, Leuven, Belgium
| | - Sara R J Gilissen
- KU Leuven, Department of Biology, Laboratory of Neuroplasticity and Neuroproteomics, Leuven, Belgium.,Leuven Brain Institute, Leuven, Belgium
| | - Lutgarde Arckens
- KU Leuven, Department of Biology, Laboratory of Neuroplasticity and Neuroproteomics, Leuven, Belgium.,Leuven Brain Institute, Leuven, Belgium
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4
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Huang S, Kirkwood A. Endocannabinoid Signaling Contributes to Experience-Induced Increase of Synaptic Release Sites From Parvalbumin Interneurons in Mouse Visual Cortex. Front Cell Neurosci 2020; 14:571133. [PMID: 33192316 PMCID: PMC7556304 DOI: 10.3389/fncel.2020.571133] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2020] [Accepted: 08/28/2020] [Indexed: 11/13/2022] Open
Abstract
During postnatal development of the visual cortex between eye-opening to puberty, visual experience promotes a gradual increase in the strength of inhibitory synaptic connections from parvalbumin-positive interneurons (PV-INs) onto layer 2/3 pyramidal cells. However, the detailed connectivity properties and molecular mechanisms underlying these developmental changes are not well understood. Using dual-patch clamp in brain slices from G42 mice, we revealed that both connection probability and the number of synaptic release sites contributed to the enhancement of synaptic strength. The increase of release site number was hindered by dark rearing from eye-opening and rescued by 3-days re-exposure to the normal visual environment. The effect of light re-exposure on restoring synaptic release sites in dark reared mice was mimicked by the agonist of cannabinoid-1 (CB1) receptors and blocked by an antagonist of these receptors, suggesting a role for endocannabinoid signaling in light-induced maturation of inhibitory connectivity from PV-INs to pyramidal cells during postnatal development.
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Affiliation(s)
- Shiyong Huang
- Program in Neuroscience, Hussman Institute for Autism, Baltimore, MD, United States.,The Mind/Brain Institute, Johns Hopkins University, Baltimore, MD, United States
| | - Alfredo Kirkwood
- The Mind/Brain Institute, Johns Hopkins University, Baltimore, MD, United States.,Department of Neuroscience, Johns Hopkins University, Baltimore, MD, United States
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Capogna M, Castillo PE, Maffei A. The ins and outs of inhibitory synaptic plasticity: Neuron types, molecular mechanisms and functional roles. Eur J Neurosci 2020; 54:6882-6901. [PMID: 32663353 DOI: 10.1111/ejn.14907] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2020] [Revised: 06/30/2020] [Accepted: 07/08/2020] [Indexed: 01/05/2023]
Abstract
GABAergic interneurons are highly diverse, and their synaptic outputs express various forms of plasticity. Compelling evidence indicates that activity-dependent changes of inhibitory synaptic transmission play a significant role in regulating neural circuits critically involved in learning and memory and circuit refinement. Here, we provide an updated overview of inhibitory synaptic plasticity with a focus on the hippocampus and neocortex. To illustrate the diversity of inhibitory interneurons, we discuss the case of two highly divergent interneuron types, parvalbumin-expressing basket cells and neurogliaform cells, which support unique roles on circuit dynamics. We also present recent progress on the molecular mechanisms underlying long-term, activity-dependent plasticity of fast inhibitory transmission. Lastly, we discuss the role of inhibitory synaptic plasticity in neuronal circuits' function. The emerging picture is that inhibitory synaptic transmission in the CNS is extremely diverse, undergoes various mechanistically distinct forms of plasticity and contributes to a much more refined computational role than initially thought. Both the remarkable diversity of inhibitory interneurons and the various forms of plasticity expressed by GABAergic synapses provide an amazingly rich inhibitory repertoire that is central to a variety of complex neural circuit functions, including memory.
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Affiliation(s)
- Marco Capogna
- Department of Biomedicine, Danish National Research Foundation Center of Excellence PROMEMO, Aarhus University, Aarhus, Denmark
| | - Pablo E Castillo
- Dominck P Purpura Department of Neuroscience, Albert Einstein College of Medicine, Bronx, NY, USA.,Department of Psychiatry and Behavioral Sciences, Albert Einstein College of Medicine, Bronx, NY, USA
| | - Arianna Maffei
- Center for Neural Circuit Dynamics and Department of Neurobiology and Behavior, Stony Brook University, Stony Brook, NY, USA
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Augustin SM, Lovinger DM. Functional Relevance of Endocannabinoid-Dependent Synaptic Plasticity in the Central Nervous System. ACS Chem Neurosci 2018; 9:2146-2161. [PMID: 29400439 DOI: 10.1021/acschemneuro.7b00508] [Citation(s) in RCA: 66] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
The endocannabinoid (eCB) signaling system plays a key role in short-term and long-term synaptic plasticity in brain regions involved in various neural functions ranging from action selection to appetite control. This review will explore the role of eCBs in shaping neural circuit function to regulate behaviors. In particular, we will discuss the behavioral consequences of eCB mediated long-term synaptic plasticity in different brain regions. This review brings together evidence from in vitro and ex vivo studies and points out the need for more in vivo studies.
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Affiliation(s)
- Shana M. Augustin
- Laboratory for Integrative Neuroscience, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Rockville, Maryland 20852, United States
| | - David M. Lovinger
- Laboratory for Integrative Neuroscience, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Rockville, Maryland 20852, United States
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Eroli F, Loonen IC, van den Maagdenberg AM, Tolner EA, Nistri A. Differential neuromodulatory role of endocannabinoids in the rodent trigeminal sensory ganglion and cerebral cortex relevant to pain processing. Neuropharmacology 2018; 131:39-50. [DOI: 10.1016/j.neuropharm.2017.12.013] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2017] [Revised: 10/19/2017] [Accepted: 12/05/2017] [Indexed: 12/21/2022]
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Li Y, Wang L, Zhang X, Huang M, Li S, Wang X, Chen L, Jiang B, Yang Y. Inhibition of Cdk5 rejuvenates inhibitory circuits and restores experience-dependent plasticity in adult visual cortex. Neuropharmacology 2017; 128:207-220. [PMID: 29031852 DOI: 10.1016/j.neuropharm.2017.10.015] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2017] [Revised: 10/02/2017] [Accepted: 10/11/2017] [Indexed: 10/18/2022]
Abstract
Cyclin-dependent kinase 5 (Cdk5) acts as an essential modulator for neural development and neurological disorders. Here we show that Cdk5 plays a pivotal role in modulating GABAergic signaling and the maturation of visual system. In adult mouse primary visual cortex, Cdk5 formed complex with the GABA synthetic enzyme glutamate decarboxylase GAD67, but not with GAD65. In addition to enhancement in the surface level of NR2B-containing NMDA receptors, inhibition of Cdk5 reduced the protein levels of GADs and Otx2, while leaving intact the expression of vesicular GABA transporter and subunits of GABAA or AMPA receptors. Whole-cell patch-clamp recording in layer II/III pyramidal neurons revealed a decrease in the frequency of miniature inhibitory postsynaptic current (mIPSC). Consequently, pharmacological inhibition and genetic knockdown of Cdk5 in adult mice led to a restoration of juvenile-like ocular dominance plasticity in vivo and long-term synaptic potential in layer II/III induced by white matter stimulation in vitro. Interestingly, we did not observe an alteration of perineuronal nets of extracellular matrix, but a reinstatement of the capability to evoke long-term depression at inhibitory synapses (iLTD), which depended on presynaptic endocannabinoid receptors and was a sign of the rejuvenated GABAergic synapses. Enhancement of GABA signaling by diazepam impeded ocular dominance plasticity rescued by Cdk5 inhibition. These results thus suggest that a physiological role of Cdk5 in visual cortex is to consolidate and stabilize neural circuits through controlling GABAergic signaling.
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Affiliation(s)
- Yue Li
- CAS Key Laboratory of Brain Function and Diseases, School of Life Sciences, University of Science and Technology of China, Hefei, Anhui 230027, China
| | - Laijian Wang
- Guangdong Province Key Laboratory of Brain Function and Disease, Faculty of Forensic Medicine, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou, Guangdong 510080, China
| | - Xinxin Zhang
- CAS Key Laboratory of Brain Function and Diseases, School of Life Sciences, University of Science and Technology of China, Hefei, Anhui 230027, China
| | - Mengyao Huang
- Guangdong Province Key Laboratory of Brain Function and Disease, Faculty of Forensic Medicine, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou, Guangdong 510080, China
| | - Sitong Li
- CAS Key Laboratory of Brain Function and Diseases, School of Life Sciences, University of Science and Technology of China, Hefei, Anhui 230027, China
| | - Xinxing Wang
- CAS Key Laboratory of Brain Function and Diseases, School of Life Sciences, University of Science and Technology of China, Hefei, Anhui 230027, China
| | - Lin Chen
- CAS Key Laboratory of Brain Function and Diseases, School of Life Sciences, University of Science and Technology of China, Hefei, Anhui 230027, China
| | - Bin Jiang
- Guangdong Province Key Laboratory of Brain Function and Disease, Faculty of Forensic Medicine, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou, Guangdong 510080, China.
| | - Yupeng Yang
- CAS Key Laboratory of Brain Function and Diseases, School of Life Sciences, University of Science and Technology of China, Hefei, Anhui 230027, China.
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Begum MR, Sng JCG. Molecular mechanisms of experience-dependent maturation in cortical GABAergic inhibition. J Neurochem 2017; 142:649-661. [PMID: 28628196 PMCID: PMC5599941 DOI: 10.1111/jnc.14103] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2017] [Revised: 06/06/2017] [Accepted: 06/09/2017] [Indexed: 12/31/2022]
Abstract
Critical periods (CP) in early post-natal life are periods of plasticity during which the neuronal circuitry is most receptive to environmental stimuli. These early experiences translate to a more permanent and sophisticated neuronal connection in the adult brain systems. Multiple studies have pointed to the development of inhibitory circuitry as one of the central factors for the onset of critical periods. We discuss several molecular mechanisms regulating inhibitory circuit maturation and CP, from gene transcription level to protein signaling level. Also, beyond the level of gene sequences, we briefly consider recent information on dynamic epigenetic regulation of gene expression through histone methylation and acetylation and their implication on timed development of the inhibitory circuitry for the onset of CP.
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Affiliation(s)
- M. Ridzwana Begum
- Department of PharmacologyYong Loo Lin School of MedicineNational University of SingaporeSingaporeSingapore
| | - Judy C. G. Sng
- Department of PharmacologyYong Loo Lin School of MedicineNational University of SingaporeSingaporeSingapore
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Brief Novel Visual Experience Fundamentally Changes Synaptic Plasticity in the Mouse Visual Cortex. J Neurosci 2017; 37:9353-9360. [PMID: 28821676 DOI: 10.1523/jneurosci.0334-17.2017] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2017] [Revised: 08/04/2017] [Accepted: 08/11/2017] [Indexed: 12/29/2022] Open
Abstract
LTP has been known to be a mechanism by which experience modifies synaptic responses in the neocortex. Visual deprivation in the form of dark exposure or dark rearing from birth enhances NMDAR-dependent LTP in layer 2/3 of visual cortex, a process often termed metaplasticity, which may involve changes in NMDAR subunit composition and function. However, the effects of reexposure to light after dark rearing from birth on LTP induction have not been explored. Here, we showed that the light exposure after dark rearing revealed a novel NMDAR independent form of LTP in the layer 2/3 pyramidal cells in visual cortex of mice of both sexes, which is dependent on mGluR5 activation and is associated with intracellular Ca2+ rise, CaMKII activity, PKC activity, and intact protein synthesis. Moreover, the capacity to induce mGluR-dependent LTP is transient: it only occurs when mice of both sexes reared in the dark from birth are exposed to light for 10-12 h, and it does not occur in vision-experienced, male mice, even after prolonged exposure to dark. Thus, the mGluR5-LTP unmasked by short visual experience can only be observed after dark rearing but not after dark exposure. These results suggested that, as in hippocampus, in layer 2/3 of visual cortex, there is coexistence of two distinct activity-dependent systems of synaptic plasticity, NMDAR-LTP, and mGluR5-LTP. The mGluR5-LTP unmasked by short visual experience may play a critical role in the faster establishment of normal receptive field properties.SIGNIFICANCE STATEMENT LTP has been known to be a mechanism by which experience modifies synaptic responses in the neocortex. Visual deprivation in the form of dark exposure or dark rearing from birth enhances NMDAR-dependent LTP in layer 2/3 of visual cortex, a process often termed metaplasticity. NMDAR-dependent form of LTP in visual cortex has been well characterized. Here, we report that an NMDAR-independent form of LTP can be promoted by novel visual experience on dark-reared mice, characterized as dependent on intracellular Ca2+ rise, PKC activity, and intact protein synthesis and also requires the activation of mGluR5. These findings suggest that, in layer 2/3 of visual cortex, as in hippocampus, there is coexistence of two distinct activity-dependent systems of synaptic plasticity.
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Expression and Function of the Endocannabinoid System in the Retina and the Visual Brain. Neural Plast 2015; 2016:9247057. [PMID: 26839718 PMCID: PMC4709729 DOI: 10.1155/2016/9247057] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2015] [Revised: 09/24/2015] [Accepted: 09/27/2015] [Indexed: 12/16/2022] Open
Abstract
Endocannabinoids are important retrograde modulators of synaptic transmission throughout the nervous system. Cannabinoid receptors are seven transmembrane G-protein coupled receptors favoring Gi/o protein. They are known to play an important role in various processes, including metabolic regulation, craving, pain, anxiety, and immune function. In the last decade, there has been a growing interest for endocannabinoids in the retina and their role in visual processing. The purpose of this review is to characterize the expression and physiological functions of the endocannabinoid system in the visual system, from the retina to the primary visual cortex, with a main interest regarding the retina, which is the best-described area in this system so far. It will show that the endocannabinoid system is widely present in the retina, mostly in the through pathway where it can modulate neurotransmitter release and ion channel activity, although some evidence also indicates possible mechanisms via amacrine, horizontal, and Müller cells. The presence of multiple endocannabinoid ligands, synthesizing and catabolizing enzymes, and receptors highlights various pharmacological targets for novel therapeutic application to retinal diseases.
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