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Rufenacht KE, Asson AJ, Hossain K, Santoro SW. The influence of olfactory experience on the birthrates of olfactory sensory neurons with specific odorant receptor identities. Genesis 2024; 62:e23611. [PMID: 38888221 PMCID: PMC11189617 DOI: 10.1002/dvg.23611] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2024] [Revised: 05/31/2024] [Accepted: 06/03/2024] [Indexed: 06/20/2024]
Abstract
Olfactory sensory neurons (OSNs) are one of a few neuron types that are generated continuously throughout life in mammals. The persistence of olfactory sensory neurogenesis beyond early development has long been thought to function simply to replace neurons that are lost or damaged through exposure to environmental insults. The possibility that olfactory sensory neurogenesis may also serve an adaptive function has received relatively little consideration, largely due to the assumption that the generation of new OSNs is stochastic with respect to OSN subtype, as defined by the single odorant receptor gene that each neural precursor stochastically chooses for expression out of hundreds of possibilities. Accordingly, the relative birthrates of different OSN subtypes are predicted to be constant and impervious to olfactory experience. This assumption has been called into question, however, by evidence that the birthrates of specific OSN subtypes can be selectively altered by manipulating olfactory experience through olfactory deprivation, enrichment, and conditioning paradigms. Moreover, studies of recovery of the OSN population following injury provide further evidence that olfactory sensory neurogenesis may not be strictly stochastic with respect to subtype. Here we review this evidence and consider mechanistic and functional implications of the prospect that specific olfactory experiences can regulate olfactory sensory neurogenesis rates in a subtype-selective manner.
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Affiliation(s)
- Karlin E Rufenacht
- Department of Pediatrics, Section of Developmental Biology, University of Colorado School of Medicine, Aurora, Colorado, USA
| | - Alexa J Asson
- Department of Pediatrics, Section of Developmental Biology, University of Colorado School of Medicine, Aurora, Colorado, USA
| | - Kawsar Hossain
- Department of Pediatrics, Section of Developmental Biology, University of Colorado School of Medicine, Aurora, Colorado, USA
| | - Stephen W Santoro
- Department of Pediatrics, Section of Developmental Biology, University of Colorado School of Medicine, Aurora, Colorado, USA
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2
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Hossain K, Smith M, Santoro SW. In mice, discrete odors can selectively promote the neurogenesis of sensory neuron subtypes that they stimulate. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.02.10.579748. [PMID: 38405728 PMCID: PMC10888860 DOI: 10.1101/2024.02.10.579748] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/27/2024]
Abstract
In mammals, olfactory sensory neurons (OSNs) are born throughout life, presumably solely to replace neurons lost via turnover or injury. This assumption follows from the hypothesis that olfactory neurogenesis is strictly stochastic with respect to neuron subtype, as defined by the single odorant receptor allele that each neural precursor stochastically chooses out of hundreds of possibilities. This hypothesis is challenged by recent findings that the birthrates of a fraction of subtypes are selectively diminished by olfactory deprivation. These findings raise questions about how, and why, olfactory stimuli are required to promote the neurogenesis of some OSN subtypes, including whether the stimuli are generic (e.g., broadly activating odors or mechanical stimuli) or specific (e.g., discrete odorants). Based on RNA-seq and scRNA-seq analyses, we hypothesized that the neurogenic stimuli are specific odorants that selectively activate the same OSN subtypes whose birthrates are accelerated. In support of this, we have found, using subtype-specific OSN birthdating, that exposure to male and musk odors can accelerate the birthrates of responsive OSNs. Collectively, our findings reveal that certain odor experiences can selectively "amplify" specific OSN subtypes, and that persistent OSN neurogenesis may serve, in part, an adaptive function.
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Affiliation(s)
- Kawsar Hossain
- Department of Pediatrics, Section of Developmental Biology, University of Colorado School of Medicine, Aurora, CO, USA
| | - Madeline Smith
- Department of Pediatrics, Section of Developmental Biology, University of Colorado School of Medicine, Aurora, CO, USA
| | - Stephen W Santoro
- Department of Pediatrics, Section of Developmental Biology, University of Colorado School of Medicine, Aurora, CO, USA
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3
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Bini de Lima AC, Sebastião da Fé VC, Palermo Hernandes MS, Oliveira dos Santos VM. Olfactory Stimulation as Environmental Enrichment for Domestic Horses-A Review. Animals (Basel) 2023; 13:3180. [PMID: 37893904 PMCID: PMC10603683 DOI: 10.3390/ani13203180] [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: 09/04/2023] [Revised: 09/18/2023] [Accepted: 09/22/2023] [Indexed: 10/29/2023] Open
Abstract
Horses constantly face several challenges inherent to the domestic environment, and it is common for the expression of their natural behavior to be drastically limited. Environmental enrichment has been suggested as an alternative to improve the captive situation of domestic horses. Among the recently proposed enrichment strategies, olfactory stimulation has emerged as a method for improving several aspects related to animal behavior. Olfaction is a sensory modality that plays a significant role in the expression of equine behavior, and in recent years, studies have shown that olfactory stimulation can influence the physiological and behavioral parameters of horses. This review provides current information on the anatomical particularities of the equine olfactory system, presents the physiological mechanisms involved in the odor detection process, and demonstrates how stress can interfere with this process. Finally, the use of olfactory stimulation as an environmental enrichment for domestic horses (Equus ferus caballus) is explored. The need for new studies that answer pertinent questions related to this topic is discussed throughout the manuscript.
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Affiliation(s)
- Ana Caroline Bini de Lima
- Nucleus of Studies in Ambience, Bioclimatology, Welfare and Ethology, Faculty of Veterinary Medicine and Animal Science, Federal University of Mato Grosso do Sul, Campo Grande 79070-900, Brazil; (V.C.S.d.F.); (M.S.P.H.); (V.M.O.d.S.)
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4
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Colombel N, Ferreira G, Sullivan RM, Coureaud G. Dynamic developmental changes in neurotransmitters supporting infant attachment learning. Neurosci Biobehav Rev 2023; 151:105249. [PMID: 37257712 PMCID: PMC10754360 DOI: 10.1016/j.neubiorev.2023.105249] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2023] [Revised: 05/15/2023] [Accepted: 05/26/2023] [Indexed: 06/02/2023]
Abstract
Infant survival relies on rapid identification, remembering and behavioral responsiveness to caregivers' sensory cues. While neural circuits supporting infant attachment learning have largely remained elusive in children, use of invasive techniques has uncovered some of its features in rodents. During a 10-day sensitive period from birth, newborn rodents associate maternal odors with maternal pleasant or noxious thermo-tactile stimulation, which gives rise to a preference and approach behavior towards these odors, and blockade of avoidance learning. Here we review the neural circuitry supporting this neonatal odor learning, unique compared to adults, focusing specifically on the early roles of neurotransmitters such as glutamate, GABA (Gamma-AminoButyric Acid), serotonin, dopamine and norepinephrine, in the olfactory bulb, the anterior piriform cortex and amygdala. The review highlights the importance of deepening our knowledge of age-specific infant brain neurotransmitters and behavioral functioning that can be translated to improve the well-being of children during typical development and aid in treatment during atypical development in childhood clinical practice, and the care during rearing of domestic animals.
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Affiliation(s)
- Nina Colombel
- Ecole Normale Supérieure de Lyon, Lyon 1 Claude Bernard University, Lyon, France
| | - Guillaume Ferreira
- FoodCircus group, NutriNeuro Lab, INRAE 1286, Bordeaux University, Bordeaux, France
| | - Regina M Sullivan
- Emotional Brain Institute, The Nathan Kline Institute, Orangeburg, NY, USA; Child and Adolescent Psychiatry, New York University Langone Medical Center, New York, USA
| | - Gérard Coureaud
- Sensory NeuroEthology Group, Lyon Neuroscience Research Center, INSERM U1028, CNRS UMR 5292, Lyon 1 University, Jean-Monnet University, Bron, France.
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5
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Maziar A, Critch TNRHY, Ghosh S, Rajani V, Flynn CM, Qin T, Reinhardt C, Man KNM, Lee A, Hell JW, Yuan Q. Aging differentially affects LTCC function in hippocampal CA1 and piriform cortex pyramidal neurons. Cereb Cortex 2023; 33:1489-1503. [PMID: 35437602 PMCID: PMC9930631 DOI: 10.1093/cercor/bhac152] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2022] [Revised: 03/25/2022] [Accepted: 03/27/2022] [Indexed: 11/14/2022] Open
Abstract
Aging is associated with cognitive decline and memory loss in humans. In rats, aging-associated neuronal excitability changes and impairments in learning have been extensively studied in the hippocampus. Here, we investigated the roles of L-type calcium channels (LTCCs) in the rat piriform cortex (PC), in comparison with those of the hippocampus. We employed spatial and olfactory tasks that involve the hippocampus and PC. LTCC blocker nimodipine administration impaired spontaneous location recognition in adult rats (6-9 months). However, the same blocker rescued the spatial learning deficiency in aged rats (19-23 months). In an odor-associative learning task, infusions of nimodipine into either the PC or dorsal CA1 impaired the ability of adult rats to learn a positive odor association. Again, in contrast, nimodipine rescued odor associative learning in aged rats. Aged CA1 neurons had higher somatic expression of LTCC Cav1.2 subunits, exhibited larger afterhyperpolarization (AHP) and lower excitability compared with adult neurons. In contrast, PC neurons from aged rats showed higher excitability and no difference in AHP. Cav1.2 expression was similar in adult and aged PC somata, but relatively higher in PSD95- puncta in aged dendrites. Our data suggest unique features of aging-associated changes in LTCCs in the PC and hippocampus.
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Affiliation(s)
- Aida Maziar
- Division of Biomedical Sciences, Faculty of Medicine, Memorial University, St. John's, NL A1B 3V6, Canada
| | - Tristian N R H Y Critch
- Division of Biomedical Sciences, Faculty of Medicine, Memorial University, St. John's, NL A1B 3V6, Canada
| | - Sourav Ghosh
- Division of Biomedical Sciences, Faculty of Medicine, Memorial University, St. John's, NL A1B 3V6, Canada
| | - Vishaal Rajani
- Division of Biomedical Sciences, Faculty of Medicine, Memorial University, St. John's, NL A1B 3V6, Canada
| | - Cassandra M Flynn
- Division of Biomedical Sciences, Faculty of Medicine, Memorial University, St. John's, NL A1B 3V6, Canada
| | - Tian Qin
- Division of Biomedical Sciences, Faculty of Medicine, Memorial University, St. John's, NL A1B 3V6, Canada
| | - Camila Reinhardt
- Division of Biomedical Sciences, Faculty of Medicine, Memorial University, St. John's, NL A1B 3V6, Canada
| | - Kwun Nok Mimi Man
- Department of Pharmacology, School of Medicine, University of California-Davis, Sacramento, CA 95817, United States
| | - Amy Lee
- Department of Neuroscience, University of Texas-Austin, Austin, TX 78712, United States
| | - Johannes W Hell
- Department of Pharmacology, School of Medicine, University of California-Davis, Sacramento, CA 95817, United States
| | - Qi Yuan
- Division of Biomedical Sciences, Faculty of Medicine, Memorial University, St. John's, NL A1B 3V6, Canada
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6
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Durand N, Aguilar P, Demondion E, Bourgeois T, Bozzolan F, Debernard S. Neuroligin 1 expression is linked to plasticity of behavioral and neuronal responses to sex pheromone in the male moth Agrotis ipsilon. J Exp Biol 2021; 224:273481. [PMID: 34647597 DOI: 10.1242/jeb.243184] [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: 07/14/2021] [Accepted: 10/07/2021] [Indexed: 11/20/2022]
Abstract
In the moth Agrotis ipsilon, the behavioral response of males to the female-emitted sex pheromone increases throughout adult life and following a prior exposure to sex pheromone, whereas it is temporally inhibited after the onset of mating. This behavioral flexibility is paralleled with changes in neuronal sensitivity to pheromone signal within the primary olfactory centers, the antennal lobes. In the present study, we tested the hypothesis that neuroligins, post-synaptic transmembrane proteins known to act as mediators of neuronal remodeling, are involved in the olfactory modulation in A. ipsilon males. We cloned a full-length cDNA encoding neuroligin 1, which is expressed predominantly in brain and especially in antennal lobes. The level of neuroligin 1 expression in antennal lobes gradually raised from day-2 until day-4 of adult life, as well as at 24 h, 48 h and 72 h following pre-exposure to sex pheromone, and the temporal dynamic of these changes correlated with increased sex pheromone responsiveness. By contrast, there was no significant variation in antennal lobe neuroligin 1 expression during the post-mating refractory period. Taken together, these results highlight that age- and odor experience-related increase in sex pheromone responsiveness is linked to the overexpression of neuroligin 1 in antennal lobes, thus suggesting a potential role played by this post-synaptic cell-adhesion molecule in mediating the plasticity of the central olfactory system in A. ipsilon.
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Affiliation(s)
- Nicolas Durand
- FRE CNRS 3498, Ecologie et Dynamique des Systèmes Anthropisés, Université de Picardie, Jules Verne, 80039 Amiens, France
| | - Paleo Aguilar
- Institute of Biology, Complutense University of Madrid, Pozuelo de Alarcon, 28223 Madrid, Spain
| | - Elodie Demondion
- Sorbonne Université, INRA, CNRS, UPEC, IRD, Univ. P7, Institute of Ecology and Environmental Sciences of Paris, 78026 Versailles, France
| | - Thomas Bourgeois
- Sorbonne Université, INRA, CNRS, UPEC, IRD, Univ. P7, Institute of Ecology and Environmental Sciences of Paris, 78026 Versailles, France
| | - Françoise Bozzolan
- Sorbonne Université, INRA, CNRS, UPEC, IRD, Univ. P7, Institute of Ecology and Environmental Sciences of Paris, 75005 Paris, France
| | - Stéphane Debernard
- Sorbonne Université, INRA, CNRS, UPEC, IRD, Univ. P7, Institute of Ecology and Environmental Sciences of Paris, 75005 Paris, France
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7
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Olfactory Stimulation Regulates the Birth of Neurons That Express Specific Odorant Receptors. Cell Rep 2021; 33:108210. [PMID: 33027656 PMCID: PMC7569022 DOI: 10.1016/j.celrep.2020.108210] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2019] [Revised: 07/03/2020] [Accepted: 09/09/2020] [Indexed: 12/18/2022] Open
Abstract
In mammals, olfactory sensory neurons (OSNs) are born throughout life, ostensibly solely to replace damaged OSNs. During differentiation, each OSN precursor “chooses,” out of hundreds of possibilities, a single odorant receptor (OR) gene, which defines the identity of the mature OSN. The relative neurogenesis rates of the hundreds of distinct OSN “subtypes” are thought to be constant, as they are determined by a stochastic process in which each OR is chosen with a fixed probability. Here, using histological, single-cell, and targeted affinity purification approaches, we show that closing one nostril in mice selectively reduces the number of newly generated OSNs of specific subtypes. Moreover, these reductions depend on an animal’s age and/or environment. Stimulation-dependent changes in the number of new OSNs are not attributable to altered rates of cell survival but rather production. Our findings indicate that the relative birth rates of distinct OSN subtypes depend on olfactory experience. In mammals, the odorant receptor identities of newly generated olfactory sensory neurons are thought to be determined by each progenitor cell’s random choice of a single receptor. Here, van der Linden et al. show that, in mice, the birth rates of neurons expressing a subset of receptors depend on olfactory stimulation.
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8
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Kermen F, Mandairon N, Chalençon L. Odor hedonics coding in the vertebrate olfactory bulb. Cell Tissue Res 2021; 383:485-493. [PMID: 33515292 PMCID: PMC7873110 DOI: 10.1007/s00441-020-03372-w] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2020] [Accepted: 11/29/2020] [Indexed: 12/21/2022]
Abstract
Whether an odorant is perceived as pleasant or unpleasant (hedonic value) governs a range of crucial behaviors: foraging, escaping danger, and social interaction. Despite its importance in olfactory perception, little is known regarding how odor hedonics is represented and encoded in the brain. Here, we review recent findings describing how odorant hedonic value is represented in the first olfaction processing center, the olfactory bulb. We discuss how olfactory bulb circuits might contribute to the coding of innate and learned odorant hedonics in addition to the odorant's physicochemical properties.
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Affiliation(s)
- Florence Kermen
- Department of Biology, Faculty of Natural Sciences, Norwegian University of Science and Technology, 7030, Trondheim, Norway.
| | - Nathalie Mandairon
- CNRS. UMR 5292: INSERM, U1028: Lyon Neuroscience Research Center Neuroplasticity and Neuropathology of Olfactory Perception Team, University Lyon, University Lyon1, F-69000, Villeurbanne, France
| | - Laura Chalençon
- CNRS. UMR 5292: INSERM, U1028: Lyon Neuroscience Research Center Neuroplasticity and Neuropathology of Olfactory Perception Team, University Lyon, University Lyon1, F-69000, Villeurbanne, France
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9
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Oruro EM, Pardo GVE, Lucion AB, Calcagnotto ME, Idiart MAP. The maturational characteristics of the GABA input in the anterior piriform cortex may also contribute to the rapid learning of the maternal odor during the sensitive period. ACTA ACUST UNITED AC 2020; 27:493-502. [PMID: 33199474 PMCID: PMC7670864 DOI: 10.1101/lm.052217.120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2020] [Accepted: 09/27/2020] [Indexed: 11/25/2022]
Abstract
During the first ten postnatal days (P), infant rodents can learn olfactory preferences for novel odors if they are paired with thermo-tactile stimuli that mimic components of maternal care. After P10, the thermo-tactile pairing becomes ineffective for conditioning. The current explanation for this change in associative learning is the alteration in the norepinephrine (NE) inputs from the locus coeruleus (LC) to the olfactory bulb (OB) and the anterior piriform cortex (aPC). By combining patch-clamp electrophysiology and computational simulations, we showed in a recent work that a transitory high responsiveness of the OB-aPC circuit to the maternal odor is an alternative mechanism that could also explain early olfactory preference learning and its cessation after P10. That result relied solely on the maturational properties of the aPC pyramidal cells. However, the GABAergic system undergoes important changes during the same period. To address the importance of the maturation of the GABAergic system for early olfactory learning, we incorporated data from the GABA inputs, obtained from in vitro patch-clamp experiment in the aPC of rat pups aged P5–P7 reported here, to the model proposed in our previous publication. In the younger than P10 OB-aPC circuit with GABA synaptic input, the number of responsive aPC pyramidal cells to the conditioned maternal odor was amplified in 30% compared to the circuit without GABAergic input. When compared with the circuit with other younger than P10 OB-aPC circuit with adult GABAergic input profile, this amplification was 88%. Together, our results suggest that during the olfactory preference learning in younger than P10, the GABAergic synaptic input presumably acts by depolarizing the aPC pyramidal neurons in such a way that it leads to the amplification of the pyramidal neurons response to the conditioned maternal odor. Furthermore, our results suggest that during this developmental period, the aPC pyramidal cells themselves seem to resolve the apparent lack of GABAergic synaptic inhibition by a strong firing adaptation in response to increased depolarizing inputs.
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Affiliation(s)
- Enver Miguel Oruro
- Neurocomputational and Language Processing Laboratory, Institute of Physics, Universidade Federal do Rio Grande do Sul, Porto Alegre, Rio Grande do Sul 91501-970, Brazil.,Neuroscience Graduate Program, Universidade Federal do Rio Grande do Sul, Porto Alegre, Rio Grande do Sul 90050-170, Brazil.,Neurophysiology and Neurochemistry of Neuronal Excitability and Synaptic Plasticity Laboratory, Department of Biochemistry, Instituto de Ciências Básicas da Saúde (ICBS), Universidade Federal do Rio Grande do Sul, Porto Alegre, Rio Grande do Sul 90035-003, Brazil
| | - Grace V E Pardo
- Neurophysiology and Neurochemistry of Neuronal Excitability and Synaptic Plasticity Laboratory, Department of Biochemistry, Instituto de Ciências Básicas da Saúde (ICBS), Universidade Federal do Rio Grande do Sul, Porto Alegre, Rio Grande do Sul 90035-003, Brazil.,Department of Physiology, ICBS, Universidade Federal do Rio Grande do Sul, Porto Alegre, Rio Grande do Sul 90050-170, Brazil.,Centre for Interdisciplinary Science and Society Studies, Universidad de Ciencias y Humanidades, Los Olivos, Lima 15314, Peru.,Center for Biomedical Research, Universidad Andina del Cusco, San Jerónimo, Cuzco 08006, Peru
| | - Aldo Bolten Lucion
- Neuroscience Graduate Program, Universidade Federal do Rio Grande do Sul, Porto Alegre, Rio Grande do Sul 90050-170, Brazil.,Department of Physiology, ICBS, Universidade Federal do Rio Grande do Sul, Porto Alegre, Rio Grande do Sul 90050-170, Brazil
| | - Maria Elisa Calcagnotto
- Neuroscience Graduate Program, Universidade Federal do Rio Grande do Sul, Porto Alegre, Rio Grande do Sul 90050-170, Brazil.,Neurophysiology and Neurochemistry of Neuronal Excitability and Synaptic Plasticity Laboratory, Department of Biochemistry, Instituto de Ciências Básicas da Saúde (ICBS), Universidade Federal do Rio Grande do Sul, Porto Alegre, Rio Grande do Sul 90035-003, Brazil
| | - Marco A P Idiart
- Neurocomputational and Language Processing Laboratory, Institute of Physics, Universidade Federal do Rio Grande do Sul, Porto Alegre, Rio Grande do Sul 91501-970, Brazil.,Neuroscience Graduate Program, Universidade Federal do Rio Grande do Sul, Porto Alegre, Rio Grande do Sul 90050-170, Brazil
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10
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Bhattarai JP, Schreck M, Moberly AH, Luo W, Ma M. Aversive Learning Increases Release Probability of Olfactory Sensory Neurons. Curr Biol 2019; 30:31-41.e3. [PMID: 31839448 DOI: 10.1016/j.cub.2019.11.006] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2019] [Revised: 10/04/2019] [Accepted: 11/01/2019] [Indexed: 10/25/2022]
Abstract
Predicting danger from previously associated sensory stimuli is essential for survival. Contributions from altered peripheral sensory inputs are implicated in this process, but the underlying mechanisms remain elusive. Here, we use the mammalian olfactory system to investigate such mechanisms. Primary olfactory sensory neurons (OSNs) project their axons directly to the olfactory bulb (OB) glomeruli, where their synaptic release is subject to local and cortical influence and neuromodulation. Pairing optogenetic activation of a single glomerulus with foot shock in mice induces freezing to light stimulation alone during fear retrieval. This is accompanied by an increase in OSN release probability and a reduction in GABAB receptor expression in the conditioned glomerulus. Furthermore, freezing time is positively correlated with the release probability of OSNs in fear-conditioned mice. These results suggest that aversive learning increases peripheral olfactory inputs at the first synapse, which may contribute to the behavioral outcome.
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Affiliation(s)
- Janardhan P Bhattarai
- Department of Neuroscience, University of Pennsylvania Perelman School of Medicine, 109 Johnson Pavilion, 3610 Hamilton Walk, Philadelphia, PA 19104, USA.
| | - Mary Schreck
- Department of Neuroscience, University of Pennsylvania Perelman School of Medicine, 109 Johnson Pavilion, 3610 Hamilton Walk, Philadelphia, PA 19104, USA
| | - Andrew H Moberly
- Department of Neuroscience, University of Pennsylvania Perelman School of Medicine, 109 Johnson Pavilion, 3610 Hamilton Walk, Philadelphia, PA 19104, USA
| | - Wenqin Luo
- Department of Neuroscience, University of Pennsylvania Perelman School of Medicine, 109 Johnson Pavilion, 3610 Hamilton Walk, Philadelphia, PA 19104, USA
| | - Minghong Ma
- Department of Neuroscience, University of Pennsylvania Perelman School of Medicine, 109 Johnson Pavilion, 3610 Hamilton Walk, Philadelphia, PA 19104, USA.
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11
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Ross JM, Bendahmane M, Fletcher ML. Olfactory Bulb Muscarinic Acetylcholine Type 1 Receptors Are Required for Acquisition of Olfactory Fear Learning. Front Behav Neurosci 2019; 13:164. [PMID: 31379534 PMCID: PMC6659260 DOI: 10.3389/fnbeh.2019.00164] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2019] [Accepted: 07/08/2019] [Indexed: 11/13/2022] Open
Abstract
The olfactory bulb (OB) receives significant cholinergic innervation and widely expresses cholinergic receptors. While acetylcholine (ACh) is essential for olfactory learning, the exact mechanisms by which ACh modulates olfactory learning and whether it is specifically required in the OB remains unknown. Using behavioral pharmacology and optogenetics, we investigated the role of OB ACh in a simple olfactory fear learning paradigm. We find that antagonizing muscarinic ACh receptors (mAChRs) in the OB during fear conditioning but not testing significantly reduces freezing to the conditioned odor, without altering olfactory abilities. Additionally, we demonstrate that m1 mAChRs, rather than m2, are required for acquisition of olfactory fear. Finally, using mice expressing channelrhodopsin in cholinergic neurons, we show that stimulating ACh release specifically in the OB during odor-shock pairing can strengthen olfactory fear learning. Together these results define a role for ACh in olfactory associative learning and OB glomerular plasticity.
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Affiliation(s)
- Jordan M. Ross
- Department of Anatomy and Neurobiology, University of Tennessee Health Science Center (UTHSC), Memphis, TN, United States
| | - Mounir Bendahmane
- Department of Pharmacology, University of Michigan, Ann Arbor, MI, United States
| | - Max L. Fletcher
- Department of Anatomy and Neurobiology, University of Tennessee Health Science Center (UTHSC), Memphis, TN, United States
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12
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Gassias E, Durand N, Demondion E, Bourgeois T, Aguilar P, Bozzolan F, Debernard S. A critical role for Dop1-mediated dopaminergic signaling in the plasticity of behavioral and neuronal responses to sex pheromone in a moth. J Exp Biol 2019; 222:jeb.211979. [DOI: 10.1242/jeb.211979] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2019] [Accepted: 10/25/2019] [Indexed: 12/22/2022]
Abstract
Most animal species, including insects, are able to modulate their responses to sexual chemosignals and this flexibility originates from the remodeling of olfactory areas under the influence of dopaminergic system. In the moth Agrotis ipsilon, the behavioral response of males to the female-emitted sex pheromone increases throughout adult life and after a prior exposure to pheromone signal and this change is accompanied by an increase in neuronal sensitivity within the primary olfactory centers, the antennal lobes (ALs). To identify the underlying neuromodulatory mechanisms, we examined whether this age- and experience-dependent olfactory plasticity is mediated by dopamine (DA) through the Dop1 receptor, an ortholog of the vertebrate D1-type dopamine receptors, which is positively coupled to adenylyl cyclase. We cloned A. ipsilon Dop1 (AiDop1) which is expressed predominantly in brain and especially in ALs and its knockdown induced decreased AL cAMP amounts and altered sex pheromone-orientated flight. The levels of DA, AiDop1 expression and cAMP in ALs increased from the third day of adult life and at 24h and 48h following pre-exposure to sex pheromone and the dynamic of these changes correlated with the increased responsiveness to sex pheromone. These results demonstrate that Dop1 is required for the display of male sexual behavior and that age- and experience-related neuronal and behavioral changes are sustained by DA-Dop1 signaling that operates within ALs probably through cAMP-dependent mechanisms in A. ipsilon. Thus, this study expands our understanding of the neuromodulatory mechanisms underlying olfactory plasticity, mechanisms that appear to be highly conserved between insects and mammals.
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Affiliation(s)
- Edmundo Gassias
- Institute of Biology, Complutense University of Madrid, Pozuelo de Alarcon, 28223 Madrid, Spain
| | - Nicolas Durand
- FRE CNRS 3498, Ecologie et Dynamique des Systèmes Anthropisés, Université de Picardie, Jules Verne, 80039 Amiens, France
| | - Elodie Demondion
- Sorbonne Université, INRA, CNRS, UPEC, IRD, Univ. P7, Institute of Ecology and Environmental Sciences of Paris, 78026 Versailles, France
| | - Thomas Bourgeois
- Sorbonne Université, INRA, CNRS, UPEC, IRD, Univ. P7, Institute of Ecology and Environmental Sciences of Paris, 78026 Versailles, France
| | - Paleo Aguilar
- Institute of Biology, Complutense University of Madrid, Pozuelo de Alarcon, 28223 Madrid, Spain
| | - Françoise Bozzolan
- Sorbonne Université, INRA, CNRS, UPEC, IRD, Univ. P7, Institute of Ecology and Environmental Sciences of Paris, 75005 Paris, France
| | - Stéphane Debernard
- Sorbonne Université, INRA, CNRS, UPEC, IRD, Univ. P7, Institute of Ecology and Environmental Sciences of Paris, 75005 Paris, France
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