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Lanthier F, Laforge J, Pflieger JF. Influence of the vestibular system on the neonatal motor behaviors in the gray short-tailed opossum ( Monodelphis domestica). IBRO Neurosci Rep 2023; 15:42-49. [PMID: 37415730 PMCID: PMC10320520 DOI: 10.1016/j.ibneur.2023.06.004] [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: 04/30/2023] [Accepted: 06/15/2023] [Indexed: 07/08/2023] Open
Abstract
Marsupials are born very immature yet must be sufficiently autonomous to crawl on the mother's belly, find a teat and attach to it to pursue their development. Sensory inputs are necessary to guide the newborn to a teat and induce attachment. The vestibular system, which perceives gravity and head movements, is one of the senses proposed to guide newborns towards the teats but there are conflicting observations about its functionality at birth (postnatal day (P) 0). To test if the vestibular system of opossum newborns is functional and can influence locomotion, we used two approaches. First, we stimulated the vestibular apparatus in in vitro preparations from opossums aged from P1 to P12 and recorded motor responses: at all ages studied, mechanical pressures applied on the vestibular organs induced spinal roots activity whereas head tilts did not induce forelimb muscle contractions. Second, using immunofluorescence, we assessed the presence of Piezo2, a protein involved in mechanotransduction in vestibular hair cells. Piezo2 labeling was scant in the utricular macula at birth, but observed in all vestibular organs at P7, its intensity increasing up to P14; it seemed to stay the same at P21. Our results indicate that neural pathways from the labyrinth to the spinal cord are already in place around birth but that the vestibular organs are too immature to influence motor activity before the end of the second postnatal week in the opossum. It may be the rule in marsupial species that the vestibular system becomes functional only after birth.
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Affiliation(s)
| | | | - Jean-François Pflieger
- Correspondence to: Département de Sciences biologiques, Université de Montréal, C.P. 6128, Succursale centre-ville, Montréal, QC H3C 3J7, Canada.
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Jan TA, Eltawil Y, Ling AH, Chen L, Ellwanger DC, Heller S, Cheng AG. Spatiotemporal dynamics of inner ear sensory and non-sensory cells revealed by single-cell transcriptomics. Cell Rep 2021; 36:109358. [PMID: 34260939 PMCID: PMC8378666 DOI: 10.1016/j.celrep.2021.109358] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2020] [Revised: 12/25/2020] [Accepted: 06/17/2021] [Indexed: 11/28/2022] Open
Abstract
The utricle is a vestibular sensory organ that requires mechanosensitive hair cells to detect linear acceleration. In neonatal mice, new hair cells are derived from non-sensory supporting cells, yet cell type diversity and mechanisms of cell addition remain poorly characterized. Here, we perform computational analyses on single-cell transcriptomes to categorize cell types and resolve 14 individual sensory and non-sensory subtypes. Along the periphery of the sensory epithelium, we uncover distinct groups of transitional epithelial cells, marked by Islr, Cnmd, and Enpep expression. By reconstructing de novo trajectories and gene dynamics, we show that as the utricle expands, Islr+ transitional epithelial cells exhibit a dynamic and proliferative phase to generate new supporting cells, followed by coordinated differentiation into hair cells. Taken together, our study reveals a sequential and coordinated process by which non-sensory epithelial cells contribute to growth of the postnatal mouse sensory epithelium. The postnatal mouse utricle expands by more than 35% and doubles its number of hair cells during the first 8 days. Using single-cell transcriptomics, Jan et al. show that the surrounding transitional epithelial cells proliferate and contribute to the expansion of the sensory epithelium through a stepwise differentiation mechanism.
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Affiliation(s)
- Taha A Jan
- Department of Otolaryngology-Head and Neck Surgery, Stanford University School of Medicine, Palo Alto, CA 94305, USA; Department of Otolaryngology-Head and Neck Surgery, University of California San Francisco, San Francisco, CA 94115, USA
| | - Yasmin Eltawil
- Department of Otolaryngology-Head and Neck Surgery, Stanford University School of Medicine, Palo Alto, CA 94305, USA
| | - Angela H Ling
- Department of Otolaryngology-Head and Neck Surgery, Stanford University School of Medicine, Palo Alto, CA 94305, USA; Department of Otolaryngology-Head and Neck Surgery, University of California San Francisco, San Francisco, CA 94115, USA
| | - Leon Chen
- Department of Otolaryngology-Head and Neck Surgery, Stanford University School of Medicine, Palo Alto, CA 94305, USA
| | - Daniel C Ellwanger
- Department of Otolaryngology-Head and Neck Surgery, Stanford University School of Medicine, Palo Alto, CA 94305, USA; Genome Analysis Unit, Amgen Research, Amgen Inc., South San Francisco, CA 94080, USA
| | - Stefan Heller
- Department of Otolaryngology-Head and Neck Surgery, Stanford University School of Medicine, Palo Alto, CA 94305, USA.
| | - Alan G Cheng
- Department of Otolaryngology-Head and Neck Surgery, Stanford University School of Medicine, Palo Alto, CA 94305, USA.
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Wang T, Niwa M, Sayyid ZN, Hosseini DK, Pham N, Jones SM, Ricci AJ, Cheng AG. Uncoordinated maturation of developing and regenerating postnatal mammalian vestibular hair cells. PLoS Biol 2019; 17:e3000326. [PMID: 31260439 PMCID: PMC6602158 DOI: 10.1371/journal.pbio.3000326] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2018] [Accepted: 05/30/2019] [Indexed: 11/18/2022] Open
Abstract
Sensory hair cells are mechanoreceptors required for hearing and balance functions. From embryonic development, hair cells acquire apical stereociliary bundles for mechanosensation, basolateral ion channels that shape receptor potential, and synaptic contacts for conveying information centrally. These key maturation steps are sequential and presumed coupled; however, whether hair cells emerging postnatally mature similarly is unknown. Here, we show that in vivo postnatally generated and regenerated hair cells in the utricle, a vestibular organ detecting linear acceleration, acquired some mature somatic features but hair bundles appeared nonfunctional and short. The utricle consists of two hair cell subtypes with distinct morphological, electrophysiological and synaptic features. In both the undamaged and damaged utricle, fate-mapping and electrophysiology experiments showed that Plp1+ supporting cells took on type II hair cell properties based on molecular markers, basolateral conductances and synaptic properties yet stereociliary bundles were absent, or small and nonfunctional. By contrast, Lgr5+ supporting cells regenerated hair cells with type I and II properties, representing a distinct hair cell precursor subtype. Lastly, direct physiological measurements showed that utricular function abolished by damage was partially regained during regeneration. Together, our data reveal a previously unrecognized aberrant maturation program for hair cells generated and regenerated postnatally and may have broad implications for inner ear regenerative therapies. During development, sensory hair cells undergo a series of critical maturation steps that are sequential and presumed coupled, but whether regenerated hair cells mature similarly is unknown. This study shows that regenerated vestibular hair cells acquired some mature somatic features, but the apical bundles remained immature.
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Affiliation(s)
- Tian Wang
- Department of Otolaryngology-Head and Neck Surgery, Stanford University School of Medicine, Stanford, California, United States of America
- Department of Otolaryngology-Head and Neck Surgery, The Second Xiangya Hospital, Central South University, Changsha, Hunan, China
| | - Mamiko Niwa
- Department of Otolaryngology-Head and Neck Surgery, Stanford University School of Medicine, Stanford, California, United States of America
| | - Zahra N. Sayyid
- Department of Otolaryngology-Head and Neck Surgery, Stanford University School of Medicine, Stanford, California, United States of America
| | - Davood K. Hosseini
- Department of Otolaryngology-Head and Neck Surgery, Stanford University School of Medicine, Stanford, California, United States of America
| | - Nicole Pham
- Department of Otolaryngology-Head and Neck Surgery, Stanford University School of Medicine, Stanford, California, United States of America
| | - Sherri M. Jones
- Department of Special Education and Communication Disorders, College of Education and Human Sciences, University of Nebraska, Lincoln, Nebraska, United States of America
| | - Anthony J. Ricci
- Department of Otolaryngology-Head and Neck Surgery, Stanford University School of Medicine, Stanford, California, United States of America
- Department of Molecular and Cellular Physiology, Stanford University School of Medicine, Stanford, California, United States of America
- * E-mail: (AGC); (AJR)
| | - Alan G. Cheng
- Department of Otolaryngology-Head and Neck Surgery, Stanford University School of Medicine, Stanford, California, United States of America
- * E-mail: (AGC); (AJR)
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Powles-Glover N, Maconochie M. Prenatal and postnatal development of the mammalian ear. Birth Defects Res 2017; 110:228-245. [DOI: 10.1002/bdr2.1167] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2017] [Revised: 10/16/2017] [Accepted: 10/28/2017] [Indexed: 12/20/2022]
Affiliation(s)
- Nicola Powles-Glover
- AstraZeneca, Innovative Medicines and Early Development; Drug Safety and Metabolism; Hertfordshire SG8 6HB United Kingdom
| | - Mark Maconochie
- Queen Mary University of London; London E1 4NS United Kingdom
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Brown DJ, Pastras CJ, Curthoys IS. Electrophysiological Measurements of Peripheral Vestibular Function-A Review of Electrovestibulography. Front Syst Neurosci 2017; 11:34. [PMID: 28620284 PMCID: PMC5450778 DOI: 10.3389/fnsys.2017.00034] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2017] [Accepted: 05/05/2017] [Indexed: 12/19/2022] Open
Abstract
Electrocochleography (EcochG), incorporating the Cochlear Microphonic (CM), the Summating Potential (SP), and the cochlear Compound Action Potential (CAP), has been used to study cochlear function in humans and experimental animals since the 1930s, providing a simple objective tool to assess both hair cell (HC) and nerve sensitivity. The vestibular equivalent of ECochG, termed here Electrovestibulography (EVestG), incorporates responses of the vestibular HCs and nerve. Few research groups have utilized EVestG to study vestibular function. Arguably, this is because stimulating the cochlea in isolation with sound is a trivial matter, whereas stimulating the vestibular system in isolation requires significantly more technical effort. That is, the vestibular system is sensitive to both high-level sound and bone-conducted vibrations, but so is the cochlea, and gross electrical responses of the inner ear to such stimuli can be difficult to interpret. Fortunately, several simple techniques can be employed to isolate vestibular electrical responses. Here, we review the literature underpinning gross vestibular nerve and HC responses, and we discuss the nomenclature used in this field. We also discuss techniques for recording EVestG in experimental animals and humans and highlight how EVestG is furthering our understanding of the vestibular system.
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Affiliation(s)
- Daniel J Brown
- Neurotology Laboratory, Sydney Medical School, The University of SydneySydney, NSW, Australia
| | - Christopher J Pastras
- Neurotology Laboratory, Sydney Medical School, The University of SydneySydney, NSW, Australia
| | - Ian S Curthoys
- Department of Psychology, The University of SydneySydney, NSW, Australia
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Johnson Chacko L, Pechriggl EJ, Fritsch H, Rask-Andersen H, Blumer MJF, Schrott-Fischer A, Glueckert R. Neurosensory Differentiation and Innervation Patterning in the Human Fetal Vestibular End Organs between the Gestational Weeks 8-12. Front Neuroanat 2016; 10:111. [PMID: 27895556 PMCID: PMC5108762 DOI: 10.3389/fnana.2016.00111] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2016] [Accepted: 10/28/2016] [Indexed: 11/13/2022] Open
Abstract
Balance orientation depends on the precise operation of the vestibular end organs and the vestibular ganglion neurons. Previous research on the assemblage of the neuronal network in the developing fetal vestibular organ has been limited to data from animal models. Insights into the molecular expression profiles and signaling moieties involved in embryological development of the human fetal inner ear have been limited. We present an investigation of the cells of the vestibular end organs with specific focus on the hair cell differentiation and innervation pattern using an uninterrupted series of unique specimens from gestational weeks 8-12. Nerve fibers positive for peripherin innervate the entire fetal crista and utricle. While in rodents only the peripheral regions of the cristae and the extra-striolar region of the statolithic organs are stained. At week 9, transcription factors PAX2 and PAX8 were observed in the hair cells whereas PAX6 was observed for the first time among the supporting cells of the cristae and the satellite glial cells of the vestibular ganglia. Glutamine synthetase, a regulator of the neurotransmitter glutamate, is strongly expressed among satellite glia cells, transitional zones of the utricle and supporting cells in the sensory epithelium. At gestational week 11, electron microscopic examination reveals bouton contacts at hair cells and first signs of the formation of a protocalyx at type I hair cells. Our study provides first-hand insight into the fetal development of the vestibular end organs as well as their pattern of innervation by means of immunohistochemical and EM techniques, with the aim of contributing toward our understanding of balance development.
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Affiliation(s)
- Lejo Johnson Chacko
- Department of Otolaryngology, Medical University of Innsbruck Innsbruck, Austria
| | - Elisabeth J Pechriggl
- Department of Anatomy, Histology, and Embryology, Division of Clinical and Functional Anatomy, Medical University of Innsbruck Innsbruck, Austria
| | - Helga Fritsch
- Department of Anatomy, Histology, and Embryology, Division of Clinical and Functional Anatomy, Medical University of Innsbruck Innsbruck, Austria
| | | | - Michael J F Blumer
- Department of Anatomy, Histology, and Embryology, Division of Clinical and Functional Anatomy, Medical University of Innsbruck Innsbruck, Austria
| | | | - Rudolf Glueckert
- Department of Otolaryngology, Medical University of InnsbruckInnsbruck, Austria; University Clinics Innsbruck, Tirol KlinikenInnsbruck, Austria
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7
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Tallot L, Doyère V, Sullivan RM. Developmental emergence of fear/threat learning: neurobiology, associations and timing. GENES, BRAIN, AND BEHAVIOR 2016; 15:144-54. [PMID: 26534899 PMCID: PMC5154388 DOI: 10.1111/gbb.12261] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/10/2015] [Revised: 10/13/2015] [Accepted: 10/15/2015] [Indexed: 02/01/2023]
Abstract
Pavlovian fear or threat conditioning, where a neutral stimulus takes on aversive properties through pairing with an aversive stimulus, has been an important tool for exploring the neurobiology of learning. In the past decades, this neurobehavioral approach has been expanded to include the developing infant. Indeed, protracted postnatal brain development permits the exploration of how incorporating the amygdala, prefrontal cortex and hippocampus into this learning system impacts the acquisition and expression of aversive conditioning. Here, we review the developmental trajectory of these key brain areas involved in aversive conditioning and relate it to pups' transition to independence through weaning. Overall, the data suggests that adult-like features of threat learning emerge as the relevant brain areas become incorporated into this learning. Specifically, the developmental emergence of the amygdala permits cue learning and the emergence of the hippocampus permits context learning. We also describe unique features of learning in early life that block threat learning and enhance interaction with the mother or exploration of the environment. Finally, we describe the development of a sense of time within this learning and its involvement in creating associations. Together these data suggest that the development of threat learning is a useful tool for dissecting adult-like functioning of brain circuits, as well as providing unique insights into ecologically relevant developmental changes.
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Affiliation(s)
- L. Tallot
- Institut des Neurosciences Paris Saclay (Neuro-PSI), UMR 9197, CNRS/Université Paris-Sud, Orsay, France
- Emotional Brain Institute, The Nathan S. Kline Institute for Psychiatric Research, Orangeburg
- Child Study Center Institute for Child and Adolescent Psychiatry, New York University Langone Medical Center, New York, NY, USA
| | - V. Doyère
- Institut des Neurosciences Paris Saclay (Neuro-PSI), UMR 9197, CNRS/Université Paris-Sud, Orsay, France
| | - R. M. Sullivan
- Emotional Brain Institute, The Nathan S. Kline Institute for Psychiatric Research, Orangeburg
- Child Study Center Institute for Child and Adolescent Psychiatry, New York University Langone Medical Center, New York, NY, USA
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8
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Wang T, Chai R, Kim GS, Pham N, Jansson L, Nguyen DH, Kuo B, May L, Zuo J, Cunningham LL, Cheng AG. Lgr5+ cells regenerate hair cells via proliferation and direct transdifferentiation in damaged neonatal mouse utricle. Nat Commun 2015; 6:6613. [PMID: 25849379 PMCID: PMC4391285 DOI: 10.1038/ncomms7613] [Citation(s) in RCA: 129] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2014] [Accepted: 02/11/2015] [Indexed: 01/10/2023] Open
Abstract
Recruitment of endogenous progenitors is critical during tissue repair. The inner ear utricle requires mechanosensory hair cells (HCs) to detect linear acceleration. After damage, non-mammalian utricles regenerate HCs via both proliferation and direct transdifferentiation. In adult mammals, limited transdifferentiation from unidentified progenitors occurs to regenerate extrastriolar Type II HCs. Here we show that HC damage in neonatal mouse utricle activates the Wnt target gene Lgr5 in striolar supporting cells. Lineage tracing and time-lapse microscopy reveal that Lgr5+ cells transdifferentiate into HC-like cells in vitro. In contrast to adults, HC ablation in neonatal utricles in vivo recruits Lgr5+ cells to regenerate striolar HCs through mitotic and transdifferentiation pathways. Both Type I and II HCs are regenerated, and regenerated HCs display stereocilia and synapses. Lastly, stabilized ß-catenin in Lgr5+ cells enhances mitotic activity and HC regeneration. Thus Lgr5 marks Wnt-regulated, damage-activated HC progenitors and may help uncover factors driving mammalian HC regeneration.
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Affiliation(s)
- Tian Wang
- Department of Otolaryngology-Head and Neck Surgery, Stanford University School of Medicine, Stanford, CA, 94305, USA
| | - Renjie Chai
- Department of Otolaryngology-Head and Neck Surgery, Stanford University School of Medicine, Stanford, CA, 94305, USA
- Key Laboratory for Developmental Genes and Human Disease, Ministry of Education, Institute of Life Sciences, Southeast University, Nanjing 210096, China
- Co-innovation Center of Neuroregeneration, Nantong University, Nantong 226001, China
| | - Grace S. Kim
- Department of Otolaryngology-Head and Neck Surgery, Stanford University School of Medicine, Stanford, CA, 94305, USA
| | - Nicole Pham
- Department of Otolaryngology-Head and Neck Surgery, Stanford University School of Medicine, Stanford, CA, 94305, USA
| | - Lina Jansson
- Department of Otolaryngology-Head and Neck Surgery, Stanford University School of Medicine, Stanford, CA, 94305, USA
| | - Duc-Huy Nguyen
- Department of Otolaryngology-Head and Neck Surgery, Stanford University School of Medicine, Stanford, CA, 94305, USA
| | - Bryan Kuo
- Department of Developmental Neurobiology, St. Jude Children’s Research Hospital, Memphis, TN, 38103, USA
| | - Lindsey May
- National Institute on Deafness and Other Communication Disorders, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Jian Zuo
- Department of Developmental Neurobiology, St. Jude Children’s Research Hospital, Memphis, TN, 38103, USA
| | - Lisa L. Cunningham
- National Institute on Deafness and Other Communication Disorders, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Alan G. Cheng
- Department of Otolaryngology-Head and Neck Surgery, Stanford University School of Medicine, Stanford, CA, 94305, USA
- Corresponding author: Alan G. Cheng, M.D., 801 Welch Road, Department of Otolaryngology-HNS, Stanford, CA 94305, Phone: (650) 725-6500, Fax: (650) 721-2163,
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Jamon M. The development of vestibular system and related functions in mammals: impact of gravity. Front Integr Neurosci 2014; 8:11. [PMID: 24570658 PMCID: PMC3916785 DOI: 10.3389/fnint.2014.00011] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2013] [Accepted: 01/20/2014] [Indexed: 12/12/2022] Open
Abstract
This chapter reviews the knowledge about the adaptation to Earth gravity during the development of mammals. The impact of early exposure to altered gravity is evaluated at the level of the functions related to the vestibular system, including postural control, homeostatic regulation, and spatial memory. The hypothesis of critical periods in the adaptation to gravity is discussed. Demonstrating a critical period requires removing the gravity stimulus during delimited time windows, what is impossible to do on Earth surface. The surgical destruction of the vestibular apparatus, and the use of mice strains with defective graviceptors have provided useful information on the consequences of missing gravity perception, and the possible compensatory mechanisms, but transitory suppression of the stimulus can only be operated during spatial flight. The rare studies on rat pups housed on board of space shuttle significantly contributed to this problem, but the use of hypergravity environment, produced by means of chronic centrifugation, is the only available tool when repeated experiments must be carried out on Earth. Even though hypergravity is sometimes considered as a mirror situation to microgravity, the two situations cannot be confused because a gravitational force is still present. The theoretical considerations that validate the paradigm of hypergravity to evaluate critical periods are discussed. The question of adaption of graviceptor is questioned from an evolutionary point of view. It is possible that graviception is hardwired, because life on Earth has evolved under the constant pressure of gravity. The rapid acquisition of motor programming by precocial mammals in minutes after birth is consistent with this hypothesis, but the slow development of motor skills in altricial species and the plasticity of vestibular perception in adults suggest that gravity experience is required for the tuning of graviceptors. The possible reasons for this dichotomy are discussed.
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Affiliation(s)
- Marc Jamon
- Faculté de Médecine de la Timone, Institut National de la Santé et de la Recherche Médicale U 1106, Aix-Marseille University Marseille, France
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Ma CW, Zhang FX, Lai CH, Lai SK, Yung KKL, Shum DKY, Chan YS. Postnatal expression of TrkB receptor in rat vestibular nuclear neurons responsive to horizontal and vertical linear accelerations. J Comp Neurol 2013; 521:612-25. [PMID: 22806574 DOI: 10.1002/cne.23193] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2011] [Revised: 10/17/2011] [Accepted: 07/09/2012] [Indexed: 11/05/2022]
Abstract
We examined the maturation expression profile of tyrosine kinase B (TrkB) receptor in rat vestibular nuclear neurons that were activated by sinusoidal linear acceleration along the horizontal or vertical axis. The otolithic origin of Fos expression in these neurons was confirmed with labyrinthectomized controls and normal controls, which showed only sporadically scattered Fos-labeled neurons in the vestibular nucleus. In P4-6 test rats, no Fos-labeled neurons were found in the vestibular nucleus, but the medial and spinal vestibular neurons showed weak immunoreactivity for TrkB. The intensity of TrkB immunoreactivity in vestibular nuclear neurons progressively increased in the second postnatal week but remained low in adults. From P7 onward, TrkB-expressing neurons responded to horizontal or vertical otolithic stimulation with Fos expression. The number of Fos-labeled vestibular nuclear neurons expressing TrkB increased with age, from 13-43% in P7 rats to 85-90% in adult rats. Our results therefore suggest that TrkB/neurotrophin signaling plays a dominant role in modulating vestibular nuclear neurons for the coding of gravity-related horizontal head movements and for the regulation of vestibular-related behavior during postnatal development.
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Affiliation(s)
- Chun-Wai Ma
- Department of Physiology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong, People's Republic of China
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11
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Bojados M, Herbin M, Jamon M. Kinematics of treadmill locomotion in mice raised in hypergravity. Behav Brain Res 2013; 244:48-57. [PMID: 23352767 DOI: 10.1016/j.bbr.2013.01.017] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2012] [Accepted: 01/14/2013] [Indexed: 11/28/2022]
Abstract
The study compared the motor performance of adult C57Bl/6J mice previously exposed to a 2G gravity environment during different periods of their development. 12 mice were housed in a large diameter centrifuge from the conception to Postnatal day 10 (P10). Another group of 10 mice was centrifuged form P10 to P30, and a third group of 9 mice was centrifuged from conception to P30. Their gait parameters, and kinematics of joint excursions were compared with 11 control mice, at the age of 2 months using a video-radiographic apparatus connected to a motorized treadmill. The mice that returned to Earth gravity level at the age of P10 showed a motor pattern similar to control mice. At variance the two groups that were centrifuged from P10 to P30 showed a different motor pattern with smaller and faster strides to walk at the same velocity as controls. On the other hand all the centrifuged mice showed significant postural changes, particularly with a more extended ankle joint, but the mice centrifuged during the whole experimental period differed even more. Our results showed that the exposure to hypergravity before P10 sufficed to modify the posture, suggesting that postural control starts before the onset of locomotion, whereas the gravity constraint perceived between P10 and P30 conditioned the tuning of quadruped locomotion with long term consequences. These results support the existence of a critical period in the acquisition of locomotion in mice.
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Affiliation(s)
- Mickael Bojados
- Aix-Marseille Univ, INSERM UMR 1106, 13385 Marseille, France
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12
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Cai J, Tuong CM, Gozal D. A neonatal mouse model of intermittent hypoxia associated with features of apnea in premature infants. Respir Physiol Neurobiol 2011; 178:210-7. [PMID: 21699999 DOI: 10.1016/j.resp.2011.06.003] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2011] [Revised: 06/08/2011] [Accepted: 06/08/2011] [Indexed: 12/13/2022]
Abstract
A neonatal mouse model of intermittent hypoxia (IH) simulating the recurring hypoxia/reoxygenation episodes of apnea of prematurity (AOP) was developed. C57BL/6 P2 pups were culled for exposure to either intermittent hypoxia or intermittent air as control. The IH paradigms consisted of alternation cycles of 20.9% O2 and either 8.0% or 5.7% O2 every 120 or 140s for 6h a day during daylight hours from day 2 to day 10 postnatally, i.e., roughly equivalent to human brain development in the perinatal period. IH exposures elicited modest to severe decrease in oxygen saturation along with bradycardia in neonatal mice, which were severity-dependent. Hypomyelination in both central and peripheral nervous systems was observed despite the absence of visible growth retardation. The neonatal mouse model of IH in this study partially fulfills the current diagnostic criteria with features of AOP, and provides opportunities to reproduce in rodents some of the pathophysiological changes associated with this disorder, such as alterations in myelination.
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Affiliation(s)
- Jun Cai
- Kosair Children's Hospital Research Institute, Department of Pediatrics, The University of Louisville School of Medicine, Louisville, KY 40202, USA.
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13
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Oei MLYM, Segenhout HM, Dijk F, Stokroos I, van der Want JJL, Albers FWJ. Functional and Anatomic Alterations in the Gentamicin-Damaged Vestibular System in the Guinea Pig. Otol Neurotol 2004; 25:57-64. [PMID: 14724494 DOI: 10.1097/00129492-200401000-00012] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
HYPOTHESIS The purpose of this study was to investigate the expected functional and morphologic effect of gentamicin on the vestibular system simultaneously by measurement of vestibular evoked potentials and electron microscopic evaluation. BACKGROUND Vestibular short-latency evoked potentials to linear acceleration have been shown to be a useful parameter of vestibular function. In gentamicin-treated animals, the morphologic damage has been well documented, although this has seldom been quantified. METHODS Fifteen guinea pigs were divided into three equal groups. Two groups received different dosages of intramuscular gentamicin for 3 weeks; the third group was the control group. Vestibular short-latency evoked potentials to linear acceleration pulses were measured. After the last gentamicin dose, the utricles were prepared for scanning and transmission electron microscopy. On scanning electron microscopy photographs, the surface area damage ratio of the utricles, a simple method of quantifying gross morphologic damage, was calculated. RESULTS The vestibular short-latency evoked potential of gentamicin-treated guinea pigs showed a slow-developing, damaging, dose-response effect on the function of the vestibular system (p = 0.01). Scanning electron microscopy and transmission electron microscopy showed severe morphologic damage in the sensory hair cells of the utricle. The surface area damage ratio showed a dose-response relationship (p = 0.01). CONCLUSION Functional and anatomic alterations in the gentamicin-damaged vestibular system in the guinea pig are related.
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MESH Headings
- Animals
- Anti-Bacterial Agents/toxicity
- Dose-Response Relationship, Drug
- Evoked Potentials, Auditory, Brain Stem/drug effects
- Female
- Gentamicins/toxicity
- Guinea Pigs
- Hair Cells, Vestibular/drug effects
- Hair Cells, Vestibular/ultrastructure
- Microscopy, Electron
- Microscopy, Electron, Scanning
- Time Factors
- Vestibule, Labyrinth/drug effects
- Vestibule, Labyrinth/physiology
- Vestibule, Labyrinth/ultrastructure
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Affiliation(s)
- Markus L Y M Oei
- Department of Otorhinolaryngology, University Hospital Groningen, Groningen, The Netherlands.
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14
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Wubbels RJ, van Marle J, Sondag HNPM, de Jong HAA. Effects of hypergravity on the morphological properties of the vestibular sensory epithelium. II. Life-long exposure of rats including embryogenesis. Brain Res Bull 2002; 58:575-80. [PMID: 12372561 DOI: 10.1016/s0361-9230(02)00828-6] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Rats were exposed to a hypergravity (HG) level of 2.5 x g from conception until the age of 14 weeks. The vestibular epithelia of four of these animals and four control animals were immunohistochemically labeled for actin and tubulin. The apical cross-sectional area of epithelial cells of HG exposed rats appeared to be larger in all end organs. Area increase was 7.0% in the utricle (p<0.005) and 8.2% in the crista (p<<0.001). Hair cells and supporting cells appeared to be intact. The cellular arrangement and the proportion of different cell types within the epithelia was normal.
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Affiliation(s)
- R J Wubbels
- Vestibular Department, ENT, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands.
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15
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Jones SM, Subramanian G, Avniel W, Guo Y, Burkard RF, Jones TA. Stimulus and recording variables and their effects on mammalian vestibular evoked potentials. J Neurosci Methods 2002; 118:23-31. [PMID: 12191754 DOI: 10.1016/s0165-0270(02)00125-5] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Linear vestibular evoked potentials (VsEPs) measure the collective neural activity of the gravity receptor organs in the inner ear that respond to linear acceleration transients. The present study examined the effects of electrode placement, analog filtering, stimulus polarity and stimulus rate on linear VsEP thresholds, latencies and amplitudes recorded from mice. Two electrode-recording montages were evaluated, rostral (forebrain) to 'mastoid' and caudal (cerebellum) to 'mastoid'. VsEP thresholds and peak latencies were identical between the two recording sites; however, peak amplitudes were larger for the caudal recording montage. VsEPs were also affected by filtering. Results suggest optimum high pass filter cutoff at 100-300 Hz, and low pass filter cutoff at 10,000 Hz. To evaluate stimulus rate, linear jerk pulses were presented at 9.2, 16, 25, 40 and 80 Hz. At 80 Hz, mean latencies were longer (0.350-0.450 ms) and mean amplitudes reduced (0.8-1.8 microV) for all response peaks. In 50% of animals, late peaks (P3, N3) disappeared at 80 Hz. The results offer options for VsEP recording protocols.
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Affiliation(s)
- Sherri M Jones
- Department of Surgery, Division of Otolaryngology, University of Missouri School of Medicine, Rm 205 Allton Bldg., DC375.00, 301 Business Loop 70W, Columbia, MO 65212, USA.
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16
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Wubbels RJ, Sondag HNPM, van Marle J, de Jong HAA. Effects of hypergravity on the morphological properties of the vestibular sensory epithelium. I. Long-term exposure of rats after full maturation of the labyrinths. Brain Res Bull 2002; 57:677-82. [PMID: 11927372 DOI: 10.1016/s0361-9230(01)00778-x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The effect of prolonged exposure to hypergravity on the morphology of vestibular epithelia of rats was investigated. At the age of 1 month, i.e., when vestibular end organs are fully maturated, three rats were transferred to a hypergravity environment of 2.5 g inside a large radius centrifuge. After 9 months, vestibular epithelia of these animals and of three control animals were immunohistochemically labeled for actin and tubulin. The apical cross-sectional area of epithelial cells of hypergravity exposed rats appeared to be smaller in all end organs. Area reduction was 1.9% in the saccule (not significant), 5.0% in the utricle (p < 0.005), and 11.6% in the crista (p<<0.001). No indications for a deterioration of vestibular functioning were observed.
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Affiliation(s)
- R J Wubbels
- Vestibular Department ENT, Academic Medical Center, University of Amsterdam, P.O.Box 22660, 1100 DD Amsterdam, The Netherlands.
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17
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Freeman S, Priner R, Mager M, Sichel JY, Perez R, Elidan J, Sohmer H. Use of evoked potentials to objectively differentiate between selective vulnerability of cochlear and vestibular end organ function. J Basic Clin Physiol Pharmacol 2001; 11:193-200. [PMID: 11041383 DOI: 10.1515/jbcpp.2000.11.3.193] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Auditory nerve brainstem evoked responses (ABR) have been used for several decades to investigate cochlear function. Recently techniques have been developed to elicit similar recordings from the vestibular end organs - short latency vestibular evoked potentials (VsEPs). Both ABR and VsEP reflect appropriate end organ function and may therefore be used to investigate the vulnerability of these end organs to various experimental insults, such as noise exposure and ototoxic drugs.
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Affiliation(s)
- S Freeman
- Department of Physiology, Hebrew University-Hadassah Medical School, Jerusalem, Israel
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