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Gomez V, Remmas W, Hernando M, Ristolainen A, Rossi C. Bioinspired Whisker Sensor for 3D Mapping of Underground Mining Environments. Biomimetics (Basel) 2024; 9:83. [PMID: 38392129 PMCID: PMC10886721 DOI: 10.3390/biomimetics9020083] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2023] [Revised: 01/24/2024] [Accepted: 01/29/2024] [Indexed: 02/24/2024] Open
Abstract
Traversing through challenging, unstructured environments, particularly in mining scenarios characterized by dust concentration, darkness, and lack of communication presents formidable obstacles for traditional sensing technologies. Drawing inspiration from naked mole rats, characterized as being skilled subterranean navigators that depend heavily on touch to navigate their environment, this study introduces a new whisker-sensing disk designed for 3D mapping in unstructured environments. The disk comprises a circular array of 32 whisker sensors, each featuring a slender flexible plastic rod attached to a compliant base housing a 3D Hall-effect sensor. The whisker sensor is modeled using both analytical and data-driven approaches to predict rotation angles based on magnetic field measurements. The validation and comparison of both models are performed by evaluating data from other whisker sensors. Additionally, a series of experiments demonstrates the whisker disk's capability in performing 3D-mapping tasks, along with successful implementation on diverse robotic platforms, highlighting its future potential for effective 3D mapping in complex and unstructured subterranean environments.
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Affiliation(s)
- Virgilio Gomez
- Centre for Automation and Robotics, Universidad Politécnica de Madrid-CSIC, 28006 Madrid, Spain
| | - Walid Remmas
- Centre for Biorobotics, Department of Computer Systems, School of Information Technologies, Tallinn University of Technology, 12618 Tallinn, Estonia
| | - Miguel Hernando
- Centre for Automation and Robotics, Universidad Politécnica de Madrid-CSIC, 28006 Madrid, Spain
| | - Asko Ristolainen
- Centre for Biorobotics, Department of Computer Systems, School of Information Technologies, Tallinn University of Technology, 12618 Tallinn, Estonia
| | - Claudio Rossi
- Centre for Automation and Robotics, Universidad Politécnica de Madrid-CSIC, 28006 Madrid, Spain
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2
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Amoroso VG, Zhao A, Vargas I, Park TJ. Naked Mole-Rats Demonstrate Profound Tolerance to Low Oxygen, High Carbon Dioxide, and Chemical Pain. Animals (Basel) 2023; 13:ani13050819. [PMID: 36899677 PMCID: PMC10000161 DOI: 10.3390/ani13050819] [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: 01/17/2023] [Revised: 02/21/2023] [Accepted: 02/21/2023] [Indexed: 03/12/2023] Open
Abstract
Naked mole-rats (Heterocephalus glaber) are very unusual among subterranean mammals in that they live in large colonies and are extremely social, spending large amounts of time gathered together in underground nests more than a meter below the surface. Many respiring individuals resting in deep, poorly ventilated nests deplete the oxygen supply and increase the concentration of carbon dioxide. Consistent with living in that atmosphere, naked mole-rats tolerate levels of low oxygen and high carbon dioxide that are deadly to most surface-dwelling mammals. Naked mole-rats appear to have evolved a number of remarkable adaptations to be able to thrive in this harsh atmosphere. In order to successfully survive low oxygen atmospheres, they conserve energy utilization by reducing the physiological activity of all organs, manifest by reduced heart rate and brain activity. Amazingly, they resort to the anaerobic metabolism of fructose rather than glucose as a fuel to generate energy when challenged by anoxia. Similarly, high carbon dioxide atmospheres normally cause tissue acidosis, while naked mole-rats have a genetic mutation preventing both acid-induced pain and pulmonary edema. Together, these putative adaptations and the tolerances they provide make the naked mole-rat an important model for studying a host of biomedical challenges.
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Affiliation(s)
- Vince G Amoroso
- Department of Biological Sciences, University of Illinois at Chicago, Chicago, IL 60607, USA
| | - Aishi Zhao
- Department of Biological Sciences, University of Illinois at Chicago, Chicago, IL 60607, USA
| | - Isabel Vargas
- Department of Biological Sciences, University of Illinois at Chicago, Chicago, IL 60607, USA
| | - Thomas J Park
- Department of Biological Sciences, University of Illinois at Chicago, Chicago, IL 60607, USA
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3
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Goyens J, Baeckens S, Smith ESJ, Pozzi J, Mason MJ. Parallel evolution of semicircular canal form and sensitivity in subterranean mammals. J Comp Physiol A Neuroethol Sens Neural Behav Physiol 2022; 208:627-640. [PMID: 36251041 DOI: 10.1007/s00359-022-01578-7] [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: 02/18/2022] [Revised: 09/19/2022] [Accepted: 09/21/2022] [Indexed: 12/14/2022]
Abstract
The vertebrate vestibular system is crucial for balance and navigation, and the evolution of its form and function in relation to species' lifestyle and mode of locomotion has been the focus of considerable recent study. Most research, however, has concentrated on aboveground mammals, with much less published on subterranean fauna. Here, we explored variation in anatomy and sensitivity of the semicircular canals among 91 mammal species, including both subterranean and non-subterranean representatives. Quantitative phylogenetically informed analyses showed significant widening of the canals relative to radius of curvature in subterranean species. A relative canal width above 0.166 indicates with 95% certainty that a species is subterranean. Fluid-structure interaction modelling predicted that canal widening leads to a substantial increase in canal sensitivity; a reasonably good estimation of the absolute sensitivity is possible based on the absolute internal canal width alone. In addition, phylogenetic comparative modelling and functional landscape exploration revealed repeated independent evolution of increased relative canal width and anterior canal sensitivity associated with the transition to a subterranean lifestyle, providing evidence of parallel adaptation. Our results suggest that living in dark, subterranean tunnels requires good balance and/or navigation skills which may be facilitated by more sensitive semicircular canals.
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Affiliation(s)
- Jana Goyens
- Laboratory of Functional Morphology, University of Antwerp, Antwerp, Belgium.
| | - Simon Baeckens
- Laboratory of Functional Morphology, University of Antwerp, Antwerp, Belgium.,Evolution and Optics of Nanostructures Lab, Department of Biology, Ghent University, Ghent, Belgium
| | | | - Jasmine Pozzi
- Laboratory of Functional Morphology, University of Antwerp, Antwerp, Belgium
| | - Matthew J Mason
- Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge, UK
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4
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Hite NJ, Sudheimer KD, Anderson L, Sarko DK. Spatial Learning and Memory in the Naked Mole-Rat: Evolutionary Adaptations to a Subterranean Niche. Front Ecol Evol 2022. [DOI: 10.3389/fevo.2022.879989] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Evolutionary adaptation to a subterranean habitat consisting of extensive underground tunnel systems would presumably require adept spatial learning and memory, however, such capabilities have not been characterized to date in naked mole-rats (Heterocephalus glaber) which, like other members of Bathyergidae, are subterranean rodents. The goal of this study was to develop a method for effectively assessing spatial learning and memory by modifying a Hebb-Williams maze for use with these subterranean rodents. Established behavioral tests to assess spatial learning and memory have primarily focused on, and have been optimized for, more typical laboratory rodent species such as mice and rats. In the current study, we utilized species-appropriate motivators, analyzed learning curves associated with maze performance, and tested memory retention in naked mole-rats. Using a modified Hebb-Williams maze, naked mole-rats underwent 3 days of training, consisting of five trials per day wherein they could freely explore the maze in search of the reward chamber. Memory retention was then tested 1 day, 1 week, and 1 month following the last day of training. Performance was analyzed based on latency to the reward chamber, errors made, and distance traveled to reach the reward chamber. Overall, this study established a behavioral paradigm for assessing maze navigation, spatial learning, and spatial memory in subterranean rodents, including optimization of rewards and environmental motivators.
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5
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Sarko DK, Reep RL. Parcellation in the dorsal column nuclei of Florida manatees (
Trichechus manatus latirostris
) and rock hyraxes (
Procavia capensis
) indicates the presence of body barrelettes. J Comp Neurol 2022; 530:2113-2131. [DOI: 10.1002/cne.25323] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2021] [Revised: 03/10/2022] [Accepted: 03/15/2022] [Indexed: 11/10/2022]
Affiliation(s)
- Diana K. Sarko
- Department of Anatomy Southern Illinois University School of Medicine Carbondale Illinois USA
| | - Roger L. Reep
- Department of Physiological Sciences University of Florida Gainesville Florida USA
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6
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Buffenstein R, Amoroso V, Andziak B, Avdieiev S, Azpurua J, Barker AJ, Bennett NC, Brieño‐Enríquez MA, Bronner GN, Coen C, Delaney MA, Dengler‐Crish CM, Edrey YH, Faulkes CG, Frankel D, Friedlander G, Gibney PA, Gorbunova V, Hine C, Holmes MM, Jarvis JUM, Kawamura Y, Kutsukake N, Kenyon C, Khaled WT, Kikusui T, Kissil J, Lagestee S, Larson J, Lauer A, Lavrenchenko LA, Lee A, Levitt JB, Lewin GR, Lewis Hardell KN, Lin TD, Mason MJ, McCloskey D, McMahon M, Miura K, Mogi K, Narayan V, O'Connor TP, Okanoya K, O'Riain MJ, Park TJ, Place NJ, Podshivalova K, Pamenter ME, Pyott SJ, Reznick J, Ruby JG, Salmon AB, Santos‐Sacchi J, Sarko DK, Seluanov A, Shepard A, Smith M, Storey KB, Tian X, Vice EN, Viltard M, Watarai A, Wywial E, Yamakawa M, Zemlemerova ED, Zions M, Smith ESJ. The naked truth: a comprehensive clarification and classification of current 'myths' in naked mole-rat biology. Biol Rev Camb Philos Soc 2022; 97:115-140. [PMID: 34476892 PMCID: PMC9277573 DOI: 10.1111/brv.12791] [Citation(s) in RCA: 36] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2021] [Revised: 08/17/2021] [Accepted: 08/18/2021] [Indexed: 12/17/2022]
Abstract
The naked mole-rat (Heterocephalus glaber) has fascinated zoologists for at least half a century. It has also generated considerable biomedical interest not only because of its extraordinary longevity, but also because of unusual protective features (e.g. its tolerance of variable oxygen availability), which may be pertinent to several human disease states, including ischemia/reperfusion injury and neurodegeneration. A recent article entitled 'Surprisingly long survival of premature conclusions about naked mole-rat biology' described 28 'myths' which, those authors claimed, are a 'perpetuation of beautiful, but falsified, hypotheses' and impede our understanding of this enigmatic mammal. Here, we re-examine each of these 'myths' based on evidence published in the scientific literature. Following Braude et al., we argue that these 'myths' fall into four main categories: (i) 'myths' that would be better described as oversimplifications, some of which persist solely in the popular press; (ii) 'myths' that are based on incomplete understanding, where more evidence is clearly needed; (iii) 'myths' where the accumulation of evidence over the years has led to a revision in interpretation, but where there is no significant disagreement among scientists currently working in the field; (iv) 'myths' where there is a genuine difference in opinion among active researchers, based on alternative interpretations of the available evidence. The term 'myth' is particularly inappropriate when applied to competing, evidence-based hypotheses, which form part of the normal evolution of scientific knowledge. Here, we provide a comprehensive critical review of naked mole-rat biology and attempt to clarify some of these misconceptions.
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Affiliation(s)
| | - Vincent Amoroso
- Department of Biological SciencesUniversity of Illinois at ChicagoChicagoIL60607U.S.A.
| | - Blazej Andziak
- Graduate Center City University of New York365 Fifth AvenueNew YorkNY10016U.S.A.
| | | | - Jorge Azpurua
- Department of AnesthesiologyStony Brook University101 Nicolls RoadStony BrookNY11794U.S.A.
| | - Alison J. Barker
- Max Delbrück Center for Molecular MedicineRobert‐Rössle‐Str 10Berlin‐Buch13092Germany
| | - Nigel C. Bennett
- Mammal Research Institute, Department of Zoology and EntomologyUniversity of PretoriaPretoria0002South Africa
| | - Miguel A. Brieño‐Enríquez
- Department of Obstetrics, Gynecology & Reproductive MedicineMagee‐Womens Research Institute204 Craft AvenuePittsburghPA15213U.S.A.
| | - Gary N. Bronner
- Department Biological SciencesRondeboschCape Town7701South Africa
| | - Clive Coen
- Reproductive Neurobiology, Division of Women's HealthSchool of Medicine, King's College LondonWestminster Bridge RoadLondonSE1 7EHU.K.
| | - Martha A. Delaney
- Zoological Pathology ProgramUniversity of Illinois3505 Veterinary Medicine Basic Sciences Building, 2001 S Lincoln AvenueUrbanaIL6180U.S.A.
| | - Christine M. Dengler‐Crish
- Department of Pharmaceutical SciencesNortheast Ohio Medical University4209 State Route 44RootstownOH44272U.S.A.
| | - Yael H. Edrey
- Northwest Vista College3535 N. Ellison DriveSan AntonioTX78251U.S.A.
| | - Chris G. Faulkes
- School of Biological and Chemical SciencesQueen Mary University of LondonMile End RoadLondonE1 4NSU.K.
| | - Daniel Frankel
- School of EngineeringNewcastle UniversityMerz CourtNewcastle Upon TyneNE1 7RUU.K.
| | - Gerard Friedlander
- Université Paris DescartesFaculté de Médecine12 Rue de l'École de MédecineParis5006France
| | - Patrick A. Gibney
- Cornell University College of Veterinary MedicineIthacaNY14853U.S.A.
| | - Vera Gorbunova
- Departments of BiologyUniversity of Rochester402 Hutchison HallRochesterNY14627U.S.A.
| | - Christopher Hine
- Cleveland ClinicLerner Research Institute9500 Euclid AvenueClevelandOH44195U.S.A.
| | - Melissa M. Holmes
- Department of PsychologyUniversity of Toronto Mississauga3359 Mississauga Road NorthMississaugaONL5L 1C6Canada
| | | | - Yoshimi Kawamura
- Department of Aging and Longevity ResearchKumamoto University1‐1‐1 HonjoKumamoto860‐0811Japan
| | - Nobuyuki Kutsukake
- Department of Evolutionary Studies of BiosystemsThe Graduate University for Advanced StudiesHayama240‐0193Japan
| | - Cynthia Kenyon
- Calico Life Sciences LLC1170 Veterans BlvdSouth San FranciscoCA94080U.S.A.
| | - Walid T. Khaled
- The School of the Biological SciencesUniversity of CambridgeTennis Court RoadCambridgeCB2 1PDU.K.
| | - Takefumi Kikusui
- Companion Animal Research, School of Veterinary MedicineAzabu UniversitySagamihara252‐5201Japan
| | - Joseph Kissil
- Department of Cancer BiologyThe Scripps Research InstituteScripps FloridaJupiterFL33458U.S.A.
| | - Samantha Lagestee
- Department of Biological SciencesUniversity of Illinois at ChicagoChicagoIL60607U.S.A.
| | - John Larson
- Department of Biological SciencesUniversity of Illinois at ChicagoChicagoIL60607U.S.A.
| | - Amanda Lauer
- Department of OtolaryngologyJohns Hopkins School of MedicineBaltimoreMD21205U.S.A.
| | - Leonid A. Lavrenchenko
- A.N. Severtsov Institute of Ecology and EvolutionRussian Academy of SciencesLeninskii pr. 33Moscow119071Russia
| | - Angela Lee
- Graduate Center City University of New York365 Fifth AvenueNew YorkNY10016U.S.A.
| | - Jonathan B. Levitt
- Biology DepartmentThe City College of New York138th Street and Convent AvenueNew YorkNY10031U.S.A.
| | - Gary R. Lewin
- Max Delbrück Center for Molecular MedicineRobert‐Rössle‐Str 10Berlin‐Buch13092Germany
| | | | - TzuHua D. Lin
- Calico Life Sciences LLC1170 Veterans BlvdSouth San FranciscoCA94080U.S.A.
| | - Matthew J. Mason
- The School of the Biological SciencesUniversity of CambridgeTennis Court RoadCambridgeCB2 1PDU.K.
| | - Dan McCloskey
- College of Staten Island in the City University of New York2800 Victory BlvdStaten IslandNY10314U.S.A.
| | - Mary McMahon
- Calico Life Sciences LLC1170 Veterans BlvdSouth San FranciscoCA94080U.S.A.
| | - Kyoko Miura
- Department of Aging and Longevity ResearchKumamoto University1‐1‐1 HonjoKumamoto860‐0811Japan
| | - Kazutaka Mogi
- Companion Animal Research, School of Veterinary MedicineAzabu UniversitySagamihara252‐5201Japan
| | - Vikram Narayan
- Calico Life Sciences LLC1170 Veterans BlvdSouth San FranciscoCA94080U.S.A.
| | | | - Kazuo Okanoya
- Department of Life SciencesThe University of Tokyo7‐3‐1 HongoTokyo153‐8902Japan
| | | | - Thomas J. Park
- Department of Biological SciencesUniversity of Illinois at ChicagoChicagoIL60607U.S.A.
| | - Ned J. Place
- Cornell University College of Veterinary MedicineIthacaNY14853U.S.A.
| | - Katie Podshivalova
- Calico Life Sciences LLC1170 Veterans BlvdSouth San FranciscoCA94080U.S.A.
| | | | - Sonja J. Pyott
- Groningen Department of OtorhinolaryngologyUniversity Medical CenterPostbus 30.001GroningenRB9700The Netherlands
| | - Jane Reznick
- Cologne Excellence Cluster for Cellular Stress Responses in Aging‐Associated Diseases (CECAD)University Hospital CologneJoseph‐Stelzmann‐Street 26Cologne50931Germany
| | - J. Graham Ruby
- Calico Life Sciences LLC1170 Veterans BlvdSouth San FranciscoCA94080U.S.A.
| | - Adam B. Salmon
- Barshop Institute for Longevity and Aging StudiesUniversity of Texas Health Science Center4939 Charles Katz Dr.San AntonioTX78229U.S.A.
| | - Joseph Santos‐Sacchi
- Department of NeuroscienceYale University School of Medicine200 South Frontage Road, SHM C‐303New HavenCT06510U.S.A.
| | - Diana K. Sarko
- Department of AnatomySchool of Medicine, Southern Illinois University975 S. NormalCarbondaleIL62901U.S.A.
| | - Andrei Seluanov
- Departments of BiologyUniversity of Rochester402 Hutchison HallRochesterNY14627U.S.A.
| | - Alyssa Shepard
- Department of Cancer BiologyThe Scripps Research InstituteScripps FloridaJupiterFL33458U.S.A.
| | - Megan Smith
- Calico Life Sciences LLC1170 Veterans BlvdSouth San FranciscoCA94080U.S.A.
| | - Kenneth B. Storey
- Department of BiologyCarleton University1125 Colonel By DriveOttawaONK1S 5B6Canada
| | - Xiao Tian
- Department of Genetics – Blavatnik InstituteHarvard Medical School77 Avenue Louis PasteurBostonMA02115U.S.A.
| | - Emily N. Vice
- Department of Biological SciencesUniversity of Illinois at ChicagoChicagoIL60607U.S.A.
| | - Mélanie Viltard
- Fondation pour la recherche en PhysiologieUniversité Catholique de LouvainClos Chapelle‐aux‐Champs 30Woluwe‐saint Lambert1200Belgium
| | - Akiyuki Watarai
- Companion Animal Research, School of Veterinary MedicineAzabu UniversitySagamihara252‐5201Japan
| | - Ewa Wywial
- Biology DepartmentThe City College of New York138th Street and Convent AvenueNew YorkNY10031U.S.A.
| | - Masanori Yamakawa
- Department of Evolutionary Studies of BiosystemsThe Graduate University for Advanced StudiesHayama240‐0193Japan
| | - Elena D. Zemlemerova
- A.N. Severtsov Institute of Ecology and EvolutionRussian Academy of SciencesLeninskii pr. 33Moscow119071Russia
| | - Michael Zions
- Graduate Center City University of New York365 Fifth AvenueNew YorkNY10016U.S.A.
| | - Ewan St. John Smith
- The School of the Biological SciencesUniversity of CambridgeTennis Court RoadCambridgeCB2 1PDU.K.
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Boublil BL, Diebold CA, Moss CF. Mechanosensory Hairs and Hair-like Structures in the Animal Kingdom: Specializations and Shared Functions Serve to Inspire Technology Applications. SENSORS (BASEL, SWITZERLAND) 2021; 21:6375. [PMID: 34640694 PMCID: PMC8512044 DOI: 10.3390/s21196375] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/27/2021] [Revised: 09/20/2021] [Accepted: 09/21/2021] [Indexed: 11/17/2022]
Abstract
Biological mechanosensation has been a source of inspiration for advancements in artificial sensory systems. Animals rely on sensory feedback to guide and adapt their behaviors and are equipped with a wide variety of sensors that carry stimulus information from the environment. Hair and hair-like sensors have evolved to support survival behaviors in different ecological niches. Here, we review the diversity of biological hair and hair-like sensors across the animal kingdom and their roles in behaviors, such as locomotion, exploration, navigation, and feeding, which point to shared functional properties of hair and hair-like structures among invertebrates and vertebrates. By reviewing research on the role of biological hair and hair-like sensors in diverse species, we aim to highlight biological sensors that could inspire the engineering community and contribute to the advancement of mechanosensing in artificial systems, such as robotics.
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Affiliation(s)
| | | | - Cynthia F. Moss
- Department of Psychological and Brain Sciences, Johns Hopkins University, 3400 N Charles St., Baltimore, MD 21218, USA; (B.L.B.); (C.A.D.)
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8
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Vice EN, Lagestee S, Browe BM, Deb D, Smith ESJ, Park TJ. Sensory Systems of the African Naked Mole-Rat. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2021; 1319:137-156. [PMID: 34424515 DOI: 10.1007/978-3-030-65943-1_5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
Naked mole-rats share some sensory characteristics with other subterraneans, including lack of object vision, retention of the ability to entrain their circadian rhythm to light, and poor hearing. On the other hand, a characteristic that may be specialized in the naked mole-rat is their exquisite orienting responses to the touch of even a single body vibrissa. They have about 100 whisker-like body vibrissae on their otherwise furless bodies. They are also insensitive to chemical and inflammatory pain, likely an adaptation to living in an atmosphere that is high in carbon dioxide, a result of many respiring individuals driving carbon dioxide accumulation. Naked mole-rats have the highest population density among subterranean mammals. High levels of carbon dioxide cause tissue acidosis and associated pain. Remarkably, naked mole-rats are completely immune to carbon dioxide-induced pulmonary edema. However, they retain the ability to detect acid as a taste (sour). Finally, their ability to smell and discriminate odors is comparable to that of rats and mice, but their vomeronasal organ, associated with sensing pheromones, is extremely small and shows a complete lack of post-natal growth. In this chapter, we review what is known about the sensory systems of the naked mole-rat with emphasis on how they differ from other mammals, and even other subterraneans. More extensive accounts of the naked mole-rat's auditory and pain systems can be found in other chapters of this book.
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Affiliation(s)
- Emily N Vice
- Laboratory of Integrative Neuroscience, Department of Biological Sciences, University of Illinois at Chicago, Chicago, IL, USA
| | - Samantha Lagestee
- Laboratory of Integrative Neuroscience, Department of Biological Sciences, University of Illinois at Chicago, Chicago, IL, USA
| | - Brigitte M Browe
- Laboratory of Integrative Neuroscience, Department of Biological Sciences, University of Illinois at Chicago, Chicago, IL, USA
| | - Deblina Deb
- Laboratory of Integrative Neuroscience, Department of Biological Sciences, University of Illinois at Chicago, Chicago, IL, USA.,Kids In Motion Pediatric Therapy Services, Highland, MI, USA
| | - Ewan St J Smith
- Department of Pharmacology, University of Cambridge, Cambridge, UK
| | - Thomas J Park
- Laboratory of Integrative Neuroscience, Department of Biological Sciences, University of Illinois at Chicago, Chicago, IL, USA.
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9
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Grant RA, Goss VGA. What can whiskers tell us about mammalian evolution, behaviour, and ecology? Mamm Rev 2021. [DOI: 10.1111/mam.12253] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Affiliation(s)
- Robyn A. Grant
- Department of Natural Sciences Manchester Metropolitan University John Dalton Building, Chester Street ManchesterM1 5GDUK
| | - Victor G. A. Goss
- School of Engineering London South Bank University Borough Road LondonSE1 0AAUK
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10
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A Review of Effects of Environment on Brain Size in Insects. INSECTS 2021; 12:insects12050461. [PMID: 34067515 PMCID: PMC8156428 DOI: 10.3390/insects12050461] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/11/2021] [Revised: 05/03/2021] [Accepted: 05/12/2021] [Indexed: 11/16/2022]
Abstract
Simple Summary What makes a big brain is fascinating since it is considered as a measure of intelligence. Above all, brain size is associated with body size. If species that have evolved with complex social behaviours possess relatively bigger brains than those deprived of such behaviours, this does not constitute the only factor affecting brain size. Other factors such as individual experience or surrounding environment also play roles in the size of the brain. In this review, I summarize the recent findings about the effects of environment on brain size in insects. I also discuss evidence about how the environment has an impact on sensory systems and influences brain size. Abstract Brain size fascinates society as well as researchers since it is a measure often associated with intelligence and was used to define species with high “intellectual capabilities”. In general, brain size is correlated with body size. However, there are disparities in terms of relative brain size between species that may be explained by several factors such as the complexity of social behaviour, the ‘social brain hypothesis’, or learning and memory capabilities. These disparities are used to classify species according to an ‘encephalization quotient’. However, environment also has an important role on the development and evolution of brain size. In this review, I summarise the recent studies looking at the effects of environment on brain size in insects, and introduce the idea that the role of environment might be mediated through the relationship between olfaction and vision. I also discussed this idea with studies that contradict this way of thinking.
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11
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The Somatosensory World of the African Naked Mole-Rat. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2021; 1319:197-220. [PMID: 34424517 DOI: 10.1007/978-3-030-65943-1_7] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
The naked mole-rat (Heterocephalus glaber) is famous for its longevity and unusual physiology. This eusocial species that lives in highly ordered and hierarchical colonies with a single breeding queen, also discovered secrets enabling somewhat pain-free living around 20 million years ago. Unlike most mammals, naked mole-rats do not feel the burn of chili pepper's active ingredient, capsaicin, nor the sting of acid. Indeed, by accumulating mutations in genes encoding proteins that are only now being exploited as targets for new pain therapies (the nerve growth factor receptor TrkA and voltage-gated sodium channel, NaV1.7), this species mastered the art of analgesia before humans evolved. Recently, we have identified pain-insensitivity as a trait shared by several closely related African mole-rat species. In this chapter we will show how African mole-rats have evolved pain insensitivity as well as discussing what the proximate factors may have been that led to the evolution of pain-free traits.
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12
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Delaney MA, Imai DM, Buffenstein R. Spontaneous Disease and Pathology of Naked Mole-Rats. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2021; 1319:353-380. [PMID: 34424525 DOI: 10.1007/978-3-030-65943-1_15] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Naked mole-rats are highly valuable research models and popular exhibition animals at zoos worldwide. Here, we provide comprehensive descriptions of common postmortem findings of naked mole-rats from both research colonies and populations managed in zoological institutions. Included are brief reviews of their natural history and related physiologic adaptations, unique anatomical features, gross and histologic lesions of common as well as rarely reported disease processes, and discussions of possible pathogeneses with recommendations for future investigations to fill knowledge gaps. Based on postmortem data of several hundreds of naked mole-rats in managed care, it is clear that cancer is extremely rare and infectious disease is infrequently reported. However, despite relatively benign aging phenotypes in this species, several degenerative processes have been nevertheless observed in older populations of naked mole-rats. As such, some potential diet and husbandry-related issues are discussed in addition to the one of the most prominent causes of morbidity and mortality, conspecific aggression and traumas. From this review of lesions and disease, it is clear that pathology, including histopathology, is integral to better understanding mechanisms of healthy aging and cancer resistance of these extraordinary rodents.
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Affiliation(s)
- Martha A Delaney
- Zoological Pathology Program, College of Veterinary Medicine, University of Illinois at Urbana-Champaign, Urbana, IL, USA.
| | - Denise M Imai
- Comparative Pathology Laboratory, School of Veterinary Medicine, University of California at Davis, Davis, CA, USA
| | - Rochelle Buffenstein
- Calico Life Sciences LLC, South San Francisco, CA, USA. .,Department of Pharmacology, University of Texas Health at San Antonio, San Antonio, TX, USA.
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Braude S, Holtze S, Begall S, Brenmoehl J, Burda H, Dammann P, Marmol D, Gorshkova E, Henning Y, Hoeflich A, Höhn A, Jung T, Hamo D, Sahm A, Shebzukhov Y, Šumbera R, Miwa S, Vyssokikh MY, Zglinicki T, Averina O, Hildebrandt TB. Surprisingly long survival of premature conclusions about naked mole‐rat biology. Biol Rev Camb Philos Soc 2020; 96:376-393. [DOI: 10.1111/brv.12660] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2020] [Revised: 10/06/2020] [Accepted: 10/13/2020] [Indexed: 12/11/2022]
Affiliation(s)
- Stan Braude
- Biology Department Washington University, One Brookings Drive St. Louis MO 63130 U.S.A
| | - Susanne Holtze
- Department of Reproduction Management Leibniz‐Institute for Zoo and Wildlife Research Berlin 10315 Germany
| | - Sabine Begall
- Department of General Zoology, Faculty of Biology University of Duisburg‐Essen, Universitätsstr Essen 45147 Germany
| | - Julia Brenmoehl
- Institute for Genome Biology Leibniz‐Institute for Farm Animal Biology Dummerstorf 18196 Germany
| | - Hynek Burda
- Department of Game Management and Wildlife Biology, Faculty of Forestry and Wood Sciences Czech University of Life Sciences Praha 16500 Czech Republic
| | - Philip Dammann
- Department of General Zoology, Faculty of Biology University of Duisburg‐Essen, Universitätsstr Essen 45147 Germany
- University Hospital Essen Hufelandstr Essen 45141 Germany
| | - Delphine Marmol
- Molecular Physiology Research Unit (URPhyM), NARILIS University of Namur Namur 5000 Belgium
| | - Ekaterina Gorshkova
- Engelhardt Institute of Molecular Biology Russian Academy of Sciences, Vavilova str. 32 Moscow 119991 Russia
- Faculty of Biology Lomonosov Moscow State University Moscow 119991 Russia
| | - Yoshiyuki Henning
- University Hospital Essen Hufelandstr Essen 45141 Germany
- Institute of Physiology Department of General Zoology University of Duisburg Essen Germany
| | - Andreas Hoeflich
- Division Signal Transduction Institute for Genome Biology, Leibniz‐Institute for Farm Animal Biology, FBN Dummerstorf, Wilhelm‐Stahl‐Allee 2 Dummerstorf 18196 Germany
| | - Annika Höhn
- Department of Molecular Toxicology German Institute of Human Nutrition (DIfE) Potsdam‐Rehbrücke Nuthetal 14558 Germany
- German Center for Diabetes Research (DZD) München‐Neuherberg 85764 Germany
| | - Tobias Jung
- Department of Molecular Toxicology German Institute of Human Nutrition (DIfE) Potsdam‐Rehbrücke Nuthetal 14558 Germany
| | - Dania Hamo
- Charité ‐ Universitätsmedizin Berlin Berlin Institute of Health Center for Regenerative Therapies (BCRT) Berlin 13353 Germany
- German Rheumatism Research Centre Berlin (DRFZ) Berlin 10117 Germany
| | - Arne Sahm
- Computational Biology Group Leibniz Institute on Aging – Fritz Lipmann Institute Jena 07745 Germany
| | - Yury Shebzukhov
- Engelhardt Institute of Molecular Biology Russian Academy of Sciences, Vavilova str. 32 Moscow 119991 Russia
- Charité ‐ Universitätsmedizin Berlin Berlin Institute of Health Center for Regenerative Therapies (BCRT) Berlin 13353 Germany
| | - Radim Šumbera
- Faculty of Science University of South Bohemia České Budějovice 37005 Czech Republic
| | - Satomi Miwa
- Biosciences Institute, Edwardson building, Campus for Ageing and Vitality Newcastle University Newcastle upon Tyne NE4 5PL U.K
| | - Mikhail Y. Vyssokikh
- Belozersky Institute of Physico‐Chemical Biology Lomonosov Moscow State University Moscow 119991 Russia
| | - Thomas Zglinicki
- Biosciences Institute, Edwardson building, Campus for Ageing and Vitality Newcastle University Newcastle upon Tyne NE4 5PL U.K
| | - Olga Averina
- Belozersky Institute of Physico‐Chemical Biology Lomonosov Moscow State University Moscow 119991 Russia
| | - Thomas B. Hildebrandt
- Department of Reproduction Management Leibniz‐Institute for Zoo and Wildlife Research Berlin 10315 Germany
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William D. Willis, Jr, MD, PhD Memorial Lecture: The evolutionary history of nerve growth factor and nociception. Pain 2020; 161 Suppl 1:S36-S47. [PMID: 33090738 PMCID: PMC7434219 DOI: 10.1097/j.pain.0000000000001889] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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15
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Endo Y, Kamei KI, Inoue-Murayama M. Genetic Signatures of Evolution of the Pluripotency Gene Regulating Network across Mammals. Genome Biol Evol 2020; 12:1806-1818. [PMID: 32780791 PMCID: PMC7643368 DOI: 10.1093/gbe/evaa169] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/05/2020] [Indexed: 01/01/2023] Open
Abstract
Mammalian pluripotent stem cells (PSCs) have distinct molecular and biological characteristics among species, but to date we lack a comprehensive understanding of regulatory network evolution in mammals. Here, we carried out a comparative genetic analysis of 134 genes constituting the pluripotency gene regulatory network across 48 mammalian species covering all the major taxonomic groups. We report that mammalian genes in the pluripotency regulatory network show a remarkably high degree of evolutionary stasis, suggesting the conservation of fundamental biological process of mammalian PSCs across species. Nevertheless, despite the overall conservation of the regulatory network, we discovered rapid evolution of the downstream targets of the core regulatory elements and specific amino acid residues that have undergone positive selection. Our data indicate development of lineage-specific pluripotency regulating networks that may explain observed variations in some characteristics of mammalian PSCs. We further revealed that positively selected genes could be associated with species' unique adaptive characteristics that were not dedicated to regulation of PSCs. These results provide important insight into the evolution of the pluripotency gene regulatory network underlying variations in characteristics of mammalian PSCs.
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Affiliation(s)
| | - Ken-ichiro Kamei
- Institute for Integrated Cell-Material Sciences (WPI-iCeMS), Kyoto University, Japan
| | - Miho Inoue-Murayama
- Wildlife Research Center, Kyoto University, Japan
- Institute for Integrated Cell-Material Sciences (WPI-iCeMS), Kyoto University, Japan
- Wildlife Genome Collaborative Research Group, National Institute for Environmental Studies, Tsukuba, Ibaraki, Japan
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16
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St. John Smith E, Park TJ. Neurobiology: Crowdsourcing CO2 to Conserve Brain Energy. Curr Biol 2020; 30:R649-R651. [DOI: 10.1016/j.cub.2020.04.009] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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Smith ESJ, Park TJ, Lewin GR. Independent evolution of pain insensitivity in African mole-rats: origins and mechanisms. J Comp Physiol A Neuroethol Sens Neural Behav Physiol 2020; 206:313-325. [PMID: 32206859 PMCID: PMC7192887 DOI: 10.1007/s00359-020-01414-w] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2019] [Revised: 02/10/2020] [Accepted: 02/27/2020] [Indexed: 12/21/2022]
Abstract
The naked mole-rat (Heterocephalus glaber) is famous for its longevity and unusual physiology. This eusocial species that lives in highly ordered and hierarchical colonies with a single breeding queen, also discovered secrets enabling somewhat pain-free living around 20 million years ago. Unlike most mammals, naked mole-rats do not feel the burn of chili pepper's active ingredient, capsaicin, nor the sting of acid. Indeed, by accumulating mutations in genes encoding proteins that are only now being exploited as targets for new pain therapies (the nerve growth factor receptor TrkA and voltage-gated sodium channel, NaV1.7), this species mastered the art of analgesia before humans evolved. Recently, we have identified pain insensitivity as a trait shared by several closely related African mole-rat species. One of these African mole-rats, the Highveld mole-rat (Cryptomys hottentotus pretoriae), is uniquely completely impervious and pain free when confronted with electrophilic compounds that activate the TRPA1 ion channel. The Highveld mole-rat has evolved a biophysical mechanism to shut down the activation of sensory neurons that drive pain. In this review, we will show how mole-rats have evolved pain insensitivity as well as discussing what the proximate factors may have been that led to the evolution of pain-free traits.
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Affiliation(s)
- Ewan St John Smith
- Department of Pharmacology, University of Cambridge, Cambridge, CB2 1PD, UK
| | - Thomas J Park
- Laboratory of Integrative Neuroscience, Department of Biological Sciences, University of Illinois at Chicago, Chicago, IL, USA
| | - Gary R Lewin
- Molecular Physiology of Somatic Sensation, Max Delbrück Center for Molecular Medicine, Robert-Rössle Str. 10, D-13125, Berlin, Germany.
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Schulze-Makuch D. The Naked Mole-Rat: An Unusual Organism with an Unexpected Latent Potential for Increased Intelligence? Life (Basel) 2019; 9:life9030076. [PMID: 31527499 PMCID: PMC6789728 DOI: 10.3390/life9030076] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2019] [Revised: 08/13/2019] [Accepted: 08/28/2019] [Indexed: 11/24/2022] Open
Abstract
Naked mole-rats are eusocial, hairless mammals that are uniquely adapted to their harsh, low-oxygen subsurface habitat. Although their encephalization quotient, a controversial marker of intelligence, is low, they exhibit many features considered tell-tale signs of highly intelligent species on our planet including longevity, plasticity, social cohesion and interaction, rudimentary language, sustainable farming abilities, and maintaining sanitary conditions in their self-built complex housing structures. It is difficult to envision how naked mole-rats would reach even higher levels of intelligence in their natural sensory-challenged habitat, but such an evolutionary path cannot be excluded if they would expand their range onto the earth’s surface.
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Affiliation(s)
- Dirk Schulze-Makuch
- Astrobiology Group, Center for Astronomy and Astrophysics (ZAA), Technical University Berlin, 10623 Berlin, Germany.
- School of the Environment, Washington State University, Pullman, WA 99163, USA.
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19
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Cain BW, Reynolds T, Sarko DK. Superficial, suprahyoid, and infrahyoid neck musculature in naked mole-rats (Heterocephalus glaber): Relative size and potential contributions to independent movement of the lower incisors. J Morphol 2019; 280:1185-1196. [PMID: 31180596 DOI: 10.1002/jmor.21022] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2019] [Revised: 05/22/2019] [Accepted: 05/24/2019] [Indexed: 11/06/2022]
Abstract
Naked mole-rats (Heterocephalus glaber) are fossorial, eusocial rodents that exhibit the unusual capability of moving their lower incisors independently in lateral and rostroventral directions. The evolution of this trait would presumably also involve concurrent alterations in neck musculature to support and control movements of the lower incisors. In order to assess morphological adaptations that might facilitate these movements, we performed detailed dissections of the neck musculature of adult naked mole-rats. In addition to characterizing attachment sites of superficial, suprahyoid, and infrahyoid musculature, we also quantified muscle mass and mandibular features thought to be associated with gape (condyle height, condyle length, and jaw length). Based on muscle attachment sites, the platysma myoides may contribute to lateral movement of the lower incisor and hemi-mandible in naked mole-rats. The large digastric muscle is likely to be a main contributor to rostroventral movement of each lower incisor. The geniohyoid and mylohyoid muscles also likely contribute to rostroventral movements of the lower incisors, and the mylohyoid may also produce lateral spreading of the hemi-mandibles. The transverse mandibular (intermandibularis) muscle likely serves to reposition the lower incisors back to a midline orientation following a movement.
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Affiliation(s)
- Blake W Cain
- Southern Illinois University School of Medicine, Department of Anatomy, Carbondale, Illinois
| | - Taylor Reynolds
- Southern Illinois University School of Medicine, Department of Anatomy, Carbondale, Illinois
| | - Diana K Sarko
- Southern Illinois University School of Medicine, Department of Anatomy, Carbondale, Illinois
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20
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Dennis JC, Stilwell NK, Smith TD, Park TJ, Bhatnagar KP, Morrison EE. Is the Mole Rat Vomeronasal Organ Functional? Anat Rec (Hoboken) 2019; 303:318-329. [DOI: 10.1002/ar.24060] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2018] [Revised: 11/02/2018] [Accepted: 12/13/2018] [Indexed: 11/06/2022]
Affiliation(s)
- John C. Dennis
- Department of Anatomy, Physiology, and Pharmacology Auburn University Auburn Alabama
| | | | - Timothy D. Smith
- School of Physical Therapy Slippery Rock University Slippery Rock Pennsylvania
- Department of Anthropology University of Pittsburgh Pittsburgh Pennsylvania
| | - Thomas J. Park
- Department of Biological Sciences University of Illinois at Chicago Chicago Illinois
| | - Kunwar P. Bhatnagar
- Department of Anatomical Sciences and Neurobiology University of Louisville School of Medicine Louisville Kentucky
| | - Edward E. Morrison
- Department of Anatomy, Physiology, and Pharmacology Auburn University Auburn Alabama
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21
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Browe BM, Vice EN, Park TJ. Naked Mole‐Rats: Blind, Naked, and Feeling No Pain. Anat Rec (Hoboken) 2018; 303:77-88. [PMID: 30365235 DOI: 10.1002/ar.23996] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2017] [Revised: 01/15/2018] [Accepted: 01/24/2018] [Indexed: 01/05/2023]
Affiliation(s)
- Brigitte M. Browe
- Department of Biological Sciences University of Illinois at Chicago, Laboratory of Integrative Neuroscience 840 West Taylor St, Chicago Illinois
| | - Emily N. Vice
- Department of Biological Sciences University of Illinois at Chicago, Laboratory of Integrative Neuroscience 840 West Taylor St, Chicago Illinois
| | - Thomas J. Park
- Department of Biological Sciences University of Illinois at Chicago, Laboratory of Integrative Neuroscience 840 West Taylor St, Chicago Illinois
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22
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Hinaux H, Devos L, Blin M, Elipot Y, Bibliowicz J, Alié A, Rétaux S. Sensory evolution in blind cavefish is driven by early embryonic events during gastrulation and neurulation. Development 2017; 143:4521-4532. [PMID: 27899509 DOI: 10.1242/dev.141291] [Citation(s) in RCA: 55] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2016] [Accepted: 10/20/2016] [Indexed: 11/20/2022]
Abstract
Natural variations in sensory systems constitute adaptive responses to the environment. Here, we compared sensory placode development in the blind cave-adapted morph and the eyed river-dwelling morph of Astyanax mexicanus Focusing on the lens and olfactory placodes, we found a trade-off between these two sensory components in the two morphs: from neural plate stage onwards, cavefish have larger olfactory placodes and smaller lens placodes. In a search for developmental mechanisms underlying cavefish sensory evolution, we analyzed the roles of Shh, Fgf8 and Bmp4 signaling, which are known to be fundamental in patterning the vertebrate head and are subtly modulated in space and time during cavefish embryogenesis. Modulating these signaling systems at the end of gastrulation shifted the balance toward a larger olfactory derivative. Olfactory tests to assess potential behavioral outcomes of such developmental evolution revealed that Astyanax cavefish are able to respond to a 105-fold lower concentration of amino acids than their surface-dwelling counterparts. We suggest that similar evolutionary developmental mechanisms may be used throughout vertebrates to drive adaptive sensory specializations according to lifestyle and habitat.
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Affiliation(s)
- Hélène Hinaux
- DECA group, Paris-Saclay Institute of Neuroscience, CNRS, Université Paris Sud, Université Paris-Saclay, Avenue de la terrasse, Gif-sur-Yvette 91198, France
| | - Lucie Devos
- DECA group, Paris-Saclay Institute of Neuroscience, CNRS, Université Paris Sud, Université Paris-Saclay, Avenue de la terrasse, Gif-sur-Yvette 91198, France
| | - Maryline Blin
- DECA group, Paris-Saclay Institute of Neuroscience, CNRS, Université Paris Sud, Université Paris-Saclay, Avenue de la terrasse, Gif-sur-Yvette 91198, France
| | - Yannick Elipot
- DECA group, Paris-Saclay Institute of Neuroscience, CNRS, Université Paris Sud, Université Paris-Saclay, Avenue de la terrasse, Gif-sur-Yvette 91198, France
| | - Jonathan Bibliowicz
- DECA group, Paris-Saclay Institute of Neuroscience, CNRS, Université Paris Sud, Université Paris-Saclay, Avenue de la terrasse, Gif-sur-Yvette 91198, France
| | - Alexandre Alié
- DECA group, Paris-Saclay Institute of Neuroscience, CNRS, Université Paris Sud, Université Paris-Saclay, Avenue de la terrasse, Gif-sur-Yvette 91198, France
| | - Sylvie Rétaux
- DECA group, Paris-Saclay Institute of Neuroscience, CNRS, Université Paris Sud, Université Paris-Saclay, Avenue de la terrasse, Gif-sur-Yvette 91198, France
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23
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Onyono PN, Kavoi BM, Kiama SG, Makanya AN. Functional Morphology of the Olfactory Mucosa and Olfactory Bulb in Fossorial Rodents: The East African Root Rat (Tachyoryctes splendens) and the Naked Mole Rat (Heterocephalus glaber). Tissue Cell 2017; 49:612-621. [PMID: 28780992 DOI: 10.1016/j.tice.2017.07.005] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2017] [Revised: 07/19/2017] [Accepted: 07/26/2017] [Indexed: 11/24/2022]
Abstract
Optimal functioning of the olfactory system is critical for survival of fossorial rodents in their subterranean lifestyle. This study examines the structure of the olfactory mucosa and olfactory bulb of two fossorial rodents exhibiting distinct social behaviors, the East African root rat and the naked mole rat. The social naked mole rat displayed simpler ethmoturbinates consisting of dorsomedial and broad discoid/flaplike parts that projected rostrally from the ethmoid bone. In the solitary root rat however, the ethmoturbinates were highly complex and exhibited elaborate branching which greatly increased the olfactory surface area. In addition, when correlated with the whole brain, the volume of the olfactory bulbs was greater in the root rat (4.24×10-2) than in the naked mole rat (3.92×10-2). Results of this study suggest that the olfactory system of the root rat is better specialized than that of the naked mole rat indicating a higher level of dependence on this system since it leads a solitary life. The naked mole rat to the contrary may have compensated for its relatively inferior olfactory system by living in groups in a social system. These findings demonstrate that structure of the olfactory system of fossorial mammals is dictated by both behavior and habitat.
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Affiliation(s)
- P N Onyono
- Department of Veterinary Anatomy and Physiology, University of Nairobi, P.O. BOX 30197-00100, Nairobi, Kenya; Department of Veterinary Anatomy and Physiology, Egerton University, P.O. BOX 536-20115, Egerton, Kenya.
| | - B M Kavoi
- Department of Veterinary Anatomy and Physiology, University of Nairobi, P.O. BOX 30197-00100, Nairobi, Kenya
| | - S G Kiama
- Department of Veterinary Anatomy and Physiology, University of Nairobi, P.O. BOX 30197-00100, Nairobi, Kenya
| | - A N Makanya
- Department of Veterinary Anatomy and Physiology, University of Nairobi, P.O. BOX 30197-00100, Nairobi, Kenya
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Jiang JJ, Cheng LH, Wu H, He YH, Kong QP. Insights into long noncoding RNAs of naked mole rat ( Heterocephalus glaber) and their potential association with cancer resistance. Epigenetics Chromatin 2016; 9:51. [PMID: 27833660 PMCID: PMC5103457 DOI: 10.1186/s13072-016-0101-5] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2016] [Accepted: 10/25/2016] [Indexed: 02/01/2023] Open
Abstract
Background Long noncoding RNAs (lncRNAs) are a class of ubiquitous noncoding RNAs and have been found to act as tumor suppressors or oncogenes, which dramatically altered our understanding of cancer. Naked mole rat (NMR, Heterocephalus glaber) is an exceptionally long-lived and cancer-resistant rodent; however, whether lncRNAs play roles in cancer resistance in this seductive species remains unknown. Results In this study, we developed a pipeline and identified a total of 4422 lncRNAs across the NMR genome based on 12 published transcriptomes. Systematic analysis revealed that NMR lncRNAs share many common characteristics with other vertebrate species, such as tissue specificity and low expression. BLASTN against with 1057 human cancer-related lncRNAs showed that only 5 NMR lncRNAs displayed homology, demonstrating the low sequence conservation between NMR lncRNAs and human cancer-related lncRNAs. Further correlation analysis of lncRNAs and protein-coding genes indicated that a total of 1295 lncRNAs were intensively coexpressed (r ≥ 0.9 or r ≤ −0.9, cP value ≤ 0.01) with potential tumor-suppressor genes in NMR, and 194 lncRNAs exhibited strong correlation (r ≥ 0.8 or r ≤ −0.8, cP value ≤ 0.01) with four high-molecular-mass hyaluronan related genes that were previously identified to play key roles in cancer resistance of NMR. Conclusion In this study, we provide the first comprehensive genome-wide analysis of NMR lncRNAs and their possible associations with cancer resistance. Our results suggest that lncRNAs may have important effects on anticancer mechanism in NMR. Electronic supplementary material The online version of this article (doi:10.1186/s13072-016-0101-5) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Jian-Jun Jiang
- State Key Laboratory of Genetic Resources and Evolution, Kunming Institute of Zoology, the Chinese Academy of Sciences, Kunming, 650223 China ; Kunming College of Life Science, University of Chinese Academy of Sciences, Beijing, 100049 China
| | - Le-Hua Cheng
- State Key Laboratory of Genetic Resources and Evolution, Kunming Institute of Zoology, the Chinese Academy of Sciences, Kunming, 650223 China ; The School of Life Science, University of Science and Technology of China, Hefei, 230027 China
| | - Huan Wu
- State Key Laboratory of Genetic Resources and Evolution, Kunming Institute of Zoology, the Chinese Academy of Sciences, Kunming, 650223 China ; Kunming College of Life Science, University of Chinese Academy of Sciences, Beijing, 100049 China
| | - Yong-Han He
- State Key Laboratory of Genetic Resources and Evolution, Kunming Institute of Zoology, the Chinese Academy of Sciences, Kunming, 650223 China
| | - Qing-Peng Kong
- State Key Laboratory of Genetic Resources and Evolution, Kunming Institute of Zoology, the Chinese Academy of Sciences, Kunming, 650223 China
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25
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Sarko DK, Rice FL, Reep RL. Elaboration and Innervation of the Vibrissal System in the Rock Hyrax (Procavia capensis). BRAIN, BEHAVIOR AND EVOLUTION 2015; 85:170-88. [PMID: 26022696 PMCID: PMC4490970 DOI: 10.1159/000381415] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/27/2014] [Accepted: 03/04/2015] [Indexed: 12/16/2022]
Abstract
Mammalian tactile hairs are commonly found on specific, restricted regions of the body, but Florida manatees represent a unique exception, exhibiting follicle-sinus complexes (FSCs, also known as vibrissae or tactile hairs) on their entire body. The orders Sirenia (including manatees and dugongs) and Hyracoidea (hyraxes) are thought to have diverged approximately 60 million years ago, yet hyraxes are among the closest relatives to sirenians. We investigated the possibility that hyraxes, like manatees, are tactile specialists with vibrissae that cover the entire postfacial body. Previous studies suggested that rock hyraxes possess postfacial vibrissae in addition to pelage hair, but this observation was not verified through histological examination. Using a detailed immunohistochemical analysis, we characterized the gross morphology, innervation and mechanoreceptors present in FSCs sampled from facial and postfacial vibrissae body regions to determine that the long postfacial hairs on the hyrax body are in fact true vibrissae. The types and relative densities of mechanoreceptors associated with each FSC also appeared to be relatively consistent between facial and postfacial FSCs. The presence of vibrissae covering the hyrax body presumably facilitates navigation in the dark caves and rocky crevices of the hyrax's environment where visual cues are limited, and may alert the animal to predatory or conspecific threats approaching the body. Furthermore, the presence of vibrissae on the postfacial body in both manatees and hyraxes indicates that this distribution may represent the ancestral condition for the supraorder Paenungulata.
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Affiliation(s)
- Diana K. Sarko
- Dept of Anatomy, Cell Biology & Physiology, Edward Via College of Osteopathic Medicine, 350 Howard Street, Spartanburg, SC 29303
| | - Frank L. Rice
- Integrated Tissue Dynamics, 7 University Place, Suite B236, Rensselaer, NY 12144
| | - Roger L. Reep
- Department of Physiological Sciences, University of Florida, Gainesville, FL 32610
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Sensory Hairs in the Bowhead Whale,Balaena mysticetus(Cetacea, Mammalia). Anat Rec (Hoboken) 2015; 298:1327-35. [DOI: 10.1002/ar.23163] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2014] [Revised: 03/04/2015] [Accepted: 03/04/2015] [Indexed: 11/07/2022]
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27
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Niederschuh SJ, Witte H, Schmidt M. The role of vibrissal sensing in forelimb position control during travelling locomotion in the rat (Rattus norvegicus, Rodentia). ZOOLOGY 2014; 118:51-62. [PMID: 25547567 DOI: 10.1016/j.zool.2014.09.003] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2014] [Revised: 09/02/2014] [Accepted: 09/03/2014] [Indexed: 11/26/2022]
Abstract
In the stem lineage of therians, a comprehensive reorganization of limb and body mechanics took place to provide dynamic stability for rapid locomotion in a highly structured environment. At what was probably the same time, mammals developed an active sense of touch in the form of movable mystacial vibrissae. The rhythmic movements of the limbs and vibrissae are controlled by central pattern-generating networks which might interact with each other in sensorimotor control. To test this possible interaction, we studied covariation between the two by investigating speed-dependent adjustments in temporal and spatial parameters of forelimb and vibrissal kinematics in the rat. Furthermore, the possible role of carpal vibrissae in connecting the two oscillating systems was explored. We compared locomotion on continuous and discontinuous substrates in the presence and absence of the mystacial or/and carpal vibrissae across a speed range of 0.2-0.5m/s and found that a close coupling of the kinematics of the two oscillating systems appears to be precluded by their differential dependence on the animal's speed. Speed-related changes in forelimb kinematics mainly occur in temporal parameters, whereas vibrissae change their spatial excursion. However, whisking frequency is always high enough that at least one whisk cycle falls into the swing phase of the limb, which is the maximum critical period for sensing the substrate on which the forepaw will be placed. The influence of tactile cues on forelimb positional control is more subtle than expected. Tactile cues appear to affect the degree of parameter variation but not average parameters or the failure rate of limbs during walking on a perforated treadmill. The carpal vibrissae appear to play a role in sensing the animal's speed by measuring the duration of the stance phase. The absence of this cue significantly reduces speed-related variation in stride frequency and vibrissal protraction.
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Stathopoulos S, Bishop JM, O’Ryan C. Genetic signatures for enhanced olfaction in the African mole-rats. PLoS One 2014; 9:e93336. [PMID: 24699281 PMCID: PMC3974769 DOI: 10.1371/journal.pone.0093336] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2013] [Accepted: 03/03/2014] [Indexed: 01/06/2023] Open
Abstract
The Olfactory Receptor (OR) superfamily, the largest in the vertebrate genome, is responsible for vertebrate olfaction and is traditionally subdivided into 17 OR families. Recent studies characterising whole-OR subgenomes revealed a 'birth and death' model of evolution for a range of species, however little is known about fine-scale evolutionary dynamics within single-OR families. This study reports the first assessment of fine-scale OR evolution and variation in African mole-rats (Bathyergidae), a family of subterranean rodents endemic to sub-Saharan Africa. Because of the selective pressures of life underground, enhanced olfaction is proposed to be fundamental to the evolutionary success of the Bathyergidae, resulting in a highly diversified OR gene-repertoire. Using a PCR-sequencing approach, we analysed variation in the OR7 family across 14 extant bathyergid species, which revealed enhanced levels of functional polymorphisms concentrated across the receptors' ligand-binding region. We propose that mole-rats are able to recognise a broad range of odorants and that this diversity is reflected throughout their OR7 gene repertoire. Using both classic tests and tree-based methods to test for signals of selection, we investigate evolutionary forces across the mole-rat OR7 gene tree. Four well-supported clades emerged in the OR phylogeny, with varying signals of selection; from neutrality to positive and purifying selection. Bathyergid life-history traits and environmental niche-specialisation are explored as possible drivers of adaptive OR evolution, emerging as non-exclusive contributors to the positive selection observed at OR7 genes. Our results reveal unexpected complexity of evolutionary mechanisms acting within a single OR family, providing insightful perspectives into OR evolutionary dynamics.
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Affiliation(s)
- Sofia Stathopoulos
- Department of Molecular and Cell Biology, University of Cape Town, Cape Town, Western Cape, South Africa
- * E-mail:
| | - Jacqueline M. Bishop
- Department of Biological Sciences, University of Cape Town, Cape Town, Western Cape, South Africa
| | - Colleen O’Ryan
- Department of Molecular and Cell Biology, University of Cape Town, Cape Town, Western Cape, South Africa
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Seki F, Hikishima K, Nambu S, Okanoya K, Okano HJ, Sasaki E, Miura K, Okano H. Multidimensional MRI-CT atlas of the naked mole-rat brain (Heterocephalus glaber). Front Neuroanat 2013; 7:45. [PMID: 24391551 PMCID: PMC3868886 DOI: 10.3389/fnana.2013.00045] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2013] [Accepted: 11/27/2013] [Indexed: 11/13/2022] Open
Abstract
Naked mole-rats have a variety of distinctive features such as the organization of a hierarchical society (known as eusociality), extraordinary longevity, and cancer resistance; thus, it would be worthwhile investigating these animals in detail. One important task is the preparation of a brain atlas database that provide comprehensive information containing multidimensional data with various image contrasts, which can be achievable using a magnetic resonance imaging (MRI). Advanced MRI techniques such as diffusion tensor imaging (DTI), which generates high contrast images of fiber structures, can characterize unique morphological properties in addition to conventional MRI. To obtain high spatial resolution images, MR histology, DTI, and X-ray computed tomography were performed on the fixed adult brain. Skull and brain structures were segmented as well as reconstructed in stereotaxic coordinates. Data were also acquired for the neonatal brain to allow developmental changes to be observed. Moreover, in vivo imaging of naked mole-rats was established as an evaluation tool of live animals. The data obtained comprised three-dimensional (3D) images with high tissue contrast as well as stereotaxic coordinates. Developmental differences in the visual system were highlighted in particular by DTI. Although it was difficult to delineate optic nerves in the mature adult brain, parts of them could be distinguished in the immature neonatal brain. From observation of cortical thickness, possibility of high somatosensory system development replaced to the visual system was indicated. 3D visualization of brain structures in the atlas as well as the establishment of in vivo imaging would promote neuroimaging researches towards detection of novel characteristics of eusocial naked mole-rats.
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Affiliation(s)
- Fumiko Seki
- Department of Physiology, Keio University School of Medicine Tokyo, Japan ; Central Institute for Experimental Animals Kanagawa, Japan
| | - Keigo Hikishima
- Department of Physiology, Keio University School of Medicine Tokyo, Japan ; Central Institute for Experimental Animals Kanagawa, Japan
| | - Sanae Nambu
- Laboratory for Symbolic Cognitive Development, RIKEN Brain Science Institute Saitama, Japan
| | - Kazuo Okanoya
- Japan Science and Technology Exploratory Research for Advanced Technology Okanoya Emotional Information Project Saitama, Japan ; Department of Life Sciences, Graduate School of Arts and Sciences, The University of Tokyo Tokyo, Japan
| | - Hirotaka J Okano
- Division of Regenerative Medicine, Jikei University School of Medicine, Tokyo, Japan
| | - Erika Sasaki
- Department of Physiology, Keio University School of Medicine Tokyo, Japan ; Central Institute for Experimental Animals Kanagawa, Japan
| | - Kyoko Miura
- Department of Physiology, Keio University School of Medicine Tokyo, Japan ; Precursory Research for Embryonic Science and Technology, Japan Science and Technology Saitama, Japan
| | - Hideyuki Okano
- Department of Physiology, Keio University School of Medicine Tokyo, Japan ; Riken Keio University Joint Research Laboratory, RIKEN Brain Science Institute Saitama, Japan
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Sarko DK, Leitch DB, Catania KC. Cutaneous and periodontal inputs to the cerebellum of the naked mole-rat (Heterocephalus glaber). Front Neuroanat 2013; 7:39. [PMID: 24302898 PMCID: PMC3831171 DOI: 10.3389/fnana.2013.00039] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2013] [Accepted: 10/25/2013] [Indexed: 11/20/2022] Open
Abstract
The naked mole-rat (Heterocephalus glaber) is a small fossorial rodent with specialized dentition that is reflected by the large cortical area dedicated to representation of the prominent incisors. Due to naked mole-rats’ behavioral reliance on the incisors for digging and for manipulating objects, as well as their ability to move the lower incisors independently, we hypothesized that expanded somatosensory representations of the incisors would be present within the cerebellum in order to accommodate a greater degree of proprioceptive, cutaneous, and periodontal input. Multiunit electrophysiological recordings targeting the ansiform lobule were used to investigate tactile inputs from receptive fields on the entire body with a focus on the incisors. Similar to other rodents, a fractured somatotopy appeared to be present with discrete representations of the same receptive fields repeated within each folium of the cerebellum. These findings confirm the presence of somatosensory inputs to a large area of the naked mole-rat cerebellum with particularly extensive representations of the lower incisors and mystacial vibrissae. We speculate that these extensive inputs facilitate processing of tactile cues as part of a sensorimotor integration network that optimizes how sensory stimuli are acquired through active exploration and in turn adjusts motor outputs (such as independent movement of the lower incisors). These results highlight the diverse sensory specializations and corresponding brain organizational schemes that have evolved in different mammals to facilitate exploration of and interaction with their environment.
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Affiliation(s)
- Diana K Sarko
- Department of Anatomy, Cell Biology and Physiology, Edward Via College of Osteopathic Medicine Spartanburg, SC, USA
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Oosthuizen MK, Scheibler AG, Charles Bennett N, Amrein I. Effects of laboratory housing on exploratory behaviour, novelty discrimination and spatial reference memory in a subterranean, solitary rodent, the Cape mole-rat (Georychus capensis). PLoS One 2013; 8:e75863. [PMID: 24040422 PMCID: PMC3770546 DOI: 10.1371/journal.pone.0075863] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2013] [Accepted: 08/22/2013] [Indexed: 11/18/2022] Open
Abstract
A large number of laboratory and field based studies are being carried out on mole-rats, both in our research group and others. Several studies have highlighted the development of adverse behaviours in laboratory animals and have emphasised the importance of enrichment for captive animals. Hence we were interested in evaluating how laboratory housing would affect behavioural performance in mole-rats. We investigated exploratory behaviour, the ability to discriminate between novel and familiar environments and reference memory in the solitary Cape mole-rat (Georychuscapensis). Our data showed that both wild and captive animals readily explore open spaces and tunnels. Wild animals were however more active than their captive counterparts. In the Y maze two trial discrimination task, wild animals failed to discriminate between novel and familiar environments, while laboratory housed mole-rats showed preferential spatial discrimination in terms of the length of time spent in the novel arm. The performance of the laboratory and wild animals were similar when tested for reference memory in the Y maze, both groups showed a significant improvement compared to the first day, from the 3rd day onwards. Wild animals made more mistakes whereas laboratory animals were slower in completing the task. The difference in performance between wild and laboratory animals in the Y-maze may be as a result of the lower activity of the laboratory animals. Laboratory maintained Cape mole-rats show classic behaviours resulting from a lack of stimulation such as reduced activity and increased aggression. However, they do display an improved novelty discrimination compared to the wild animals. Slower locomotion rate of the laboratory animals may increase the integration time of stimuli, hence result in a more thorough inspection of the surroundings. Unlike the captive animals, wild animals show flexibility in their responses to unpredictable events, which is an important requirement under natural living conditions.
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Affiliation(s)
| | | | - Nigel Charles Bennett
- Department of Zoology and Entomology, University of Pretoria, Pretoria, South Africa
| | - Irmgard Amrein
- Department of Anatomy, University of Zurich, Zürich, Switzerland
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Gaspard JC, Bauer GB, Reep RL, Dziuk K, Read L, Mann DA. Detection of hydrodynamic stimuli by the Florida manatee (Trichechus manatus latirostris). J Comp Physiol A Neuroethol Sens Neural Behav Physiol 2013; 199:441-50. [DOI: 10.1007/s00359-013-0822-x] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2012] [Revised: 04/15/2013] [Accepted: 04/16/2013] [Indexed: 10/26/2022]
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Abstract
The hairs of the skin not only function to prevent heat loss but also have important sensory functions. Recent work has now established that each hair of the skin is innervated by one or more of three types of mechanoreceptor ending. Each of these three mechanoreceptor types possesses distinct molecular features and detects distinctive information about skin touch, which is relayed to specific brain locations in a somatotopic fashion.
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Affiliation(s)
- Stefan G. Lechner
- Department of Neuroscience, Max Delbrück Center for Molecular Medicine, Berlin, Germany
| | - Gary R. Lewin
- Department of Neuroscience, Max Delbrück Center for Molecular Medicine, Berlin, Germany
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St John Smith E, Purfürst B, Grigoryan T, Park TJ, Bennett NC, Lewin GR. Specific paucity of unmyelinated C-fibers in cutaneous peripheral nerves of the African naked-mole rat: comparative analysis using six species of Bathyergidae. J Comp Neurol 2013; 520:2785-803. [PMID: 22528859 PMCID: PMC3410526 DOI: 10.1002/cne.23133] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
In mammalian peripheral nerves, unmyelinated C-fibers usually outnumber myelinated A-fibers. By using transmission electron microscopy, we recently showed that the saphenous nerve of the naked mole-rat (Heterocephalus glaber) has a C-fiber deficit manifested as a substantially lower C:A-fiber ratio compared with other mammals. Here we determined the uniqueness of this C-fiber deficit by performing a quantitative anatomical analysis of several peripheral nerves in five further members of the Bathyergidae mole-rat family: silvery (Heliophobius argenteocinereus), giant (Fukomys mechowii), Damaraland (Fukomys damarensis), Mashona (Fukomys darlingi), and Natal (Cryptomys hottentotus natalensis) mole-rats. In the largely cutaneous saphenous and sural nerves, the naked mole-rat had the lowest C:A-fiber ratio (∼1.5:1 compared with ∼3:1), whereas, in nerves innervating both skin and muscle (common peroneal and tibial) or just muscle (lateral/medial gastrocnemius), this pattern was mostly absent. We asked whether lack of hair follicles alone accounts for the C-fiber paucity by using as a model a mouse that loses virtually all its hair as a consequence of conditional deletion of the β-catenin gene in the skin. These β-catenin loss-of function mice (β-cat LOF mice) displayed only a mild decrease in C:A-fiber ratio compared with wild-type mice (4.42 compared with 3.81). We suggest that the selective cutaneous C-fiber deficit in the cutaneous nerves of naked mole-rats is unlikely to be due primarily to lack of skin hair follicles. Possible mechanisms contributing to this unique peripheral nerve anatomy are discussed.
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Affiliation(s)
- Ewan St John Smith
- Department of Neuroscience, Max-Delbrück Center for Molecular Medicine, D 13125 Berlin, Germany
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Muchlinski MN, Durham EL, Smith TD, Burrows AM. Comparative histomorphology of intrinsic vibrissa musculature among primates: implications for the evolution of sensory ecology and “face touch”. AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY 2012; 150:301-12. [DOI: 10.1002/ajpa.22206] [Citation(s) in RCA: 60] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/14/2012] [Accepted: 11/08/2012] [Indexed: 11/06/2022]
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Peterson BL, Larson J, Buffenstein R, Park TJ, Fall CP. Blunted neuronal calcium response to hypoxia in naked mole-rat hippocampus. PLoS One 2012; 7:e31568. [PMID: 22363676 PMCID: PMC3283646 DOI: 10.1371/journal.pone.0031568] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2011] [Accepted: 01/13/2012] [Indexed: 01/09/2023] Open
Abstract
Naked mole-rats are highly social and strictly subterranean rodents that live in large communal colonies in sealed and chronically oxygen-depleted burrows. Brain slices from naked mole-rats show extreme tolerance to hypoxia compared to slices from other mammals, as indicated by maintenance of synaptic transmission under more hypoxic conditions and three fold longer latency to anoxic depolarization. A key factor in determining whether or not the cellular response to hypoxia is reversible or leads to cell death may be the elevation of intracellular calcium concentration. In the present study, we used fluorescent imaging techniques to measure relative intracellular calcium changes in CA1 pyramidal cells of hippocampal slices during hypoxia. We found that calcium accumulation during hypoxia was significantly and substantially attenuated in slices from naked mole-rats compared to slices from laboratory mice. This was the case for both neonatal (postnatal day 6) and older (postnatal day 20) age groups. Furthermore, while both species demonstrated more calcium accumulation at older ages, the older naked mole-rats showed a smaller calcium accumulation response than even the younger mice. A blunted intracellular calcium response to hypoxia may contribute to the extreme hypoxia tolerance of naked mole-rat neurons. The results are discussed in terms of a general hypothesis that a very prolonged or arrested developmental process may allow adult naked mole-rat brain to retain the hypoxia tolerance normally only seen in neonatal mammals.
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Affiliation(s)
- Bethany L. Peterson
- Department of Biological Sciences, University of Illinois at Chicago, Chicago, Illinois, United States of America
| | - John Larson
- Department of Biological Sciences, University of Illinois at Chicago, Chicago, Illinois, United States of America
- Laboratory of Integrative Neuroscience, University of Illinois at Chicago, Chicago, Illinois, United States of America
- Psychiatric Institute, Department of Psychiatry, University of Illinois at Chicago, Chicago, Illinois, United States of America
| | - Rochelle Buffenstein
- Barshop Institute and Department of Physiology, University of Texas Health Science Center at San Antonio, San Antonio, Texas, United States of America
| | - Thomas J. Park
- Department of Biological Sciences, University of Illinois at Chicago, Chicago, Illinois, United States of America
- Laboratory of Integrative Neuroscience, University of Illinois at Chicago, Chicago, Illinois, United States of America
| | - Christopher P. Fall
- Department of BioEngineering, University of Illinois at Chicago, Chicago, Illinois, United States of America
- Department of Computer Science, Georgetown University, Washington, D. C., United States of America
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Abstract
Naked mole rats are mouse-sized rodents that have become an important animal model in biomedical research. They play a unique mammalian role in behavioral and ecophysiological research of life underground. This chapter studies the general physiology, anatomy of organ systems, husbandry, and uses in research of the naked mole rats. Naked mole rats belong to the order Rodentia in that they have two incisor teeth on the upper and lower arcade that continuously grow. The skin is loose, wrinkled, and brownish pink in color. The body is for the most part absent of hairs with the exception of tactile hairs that are regularly arranged throughout the body and which are particularly prominent around the face and to a lesser extent on the tail. They are typically housed at 28–30°C, and at 50–60% relative humidity. Because naked mole rats are social and have cooperative behaviors, the study of their conduct has more applicability to people. The chapter describes the models of experimental research on the naked mole rat such as the model of reproductive suppression, model of somatosensory processing, model of bone elongation, and model of aging.
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Brecht M, Naumann R, Anjum F, Wolfe J, Munz M, Mende C, Roth-Alpermann C. The neurobiology of Etruscan shrew active touch. Philos Trans R Soc Lond B Biol Sci 2011; 366:3026-36. [PMID: 21969684 PMCID: PMC3172601 DOI: 10.1098/rstb.2011.0160] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
The Etruscan shrew, Suncus etruscus, is not only the smallest terrestrial mammal, but also one of the fastest and most tactile hunters described to date. The shrew's skeletal muscle consists entirely of fast-twitch types and lacks slow fibres. Etruscan shrews detect, overwhelm, and kill insect prey in large numbers in darkness. The cricket prey is exquisitely mechanosensitive and fast-moving, and is as big as the shrew itself. Experiments with prey replica show that shape cues are both necessary and sufficient for evoking attacks. Shrew attacks are whisker guided by motion- and size-invariant Gestalt-like prey representations. Shrews often attack their prey prior to any signs of evasive manoeuvres. Shrews whisk at frequencies of approximately 14 Hz and can react with latencies as short as 25-30 ms to prey movement. The speed of attacks suggests that shrews identify and classify prey with a single touch. Large parts of the shrew's brain respond to vibrissal touch, which is represented in at least four cortical areas comprising collectively about a third of the cortical volume. Etruscan shrews can enter a torpid state and reduce their body temperature; we observed that cortical response latencies become two to three times longer when body temperature drops from 36°C to 24°C, suggesting that endothermy contributes to the animal's high-speed sensorimotor performance. We argue that small size, high-speed behaviour and extreme dependence on touch are not coincidental, but reflect an evolutionary strategy, in which the metabolic costs of small body size are outweighed by the advantages of being a short-range high-speed touch and kill predator.
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Affiliation(s)
- Michael Brecht
- BCCN, Humboldt University Berlin, Philippstrasse 13, House 6, 10115 Berlin, Germany.
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Sarko DK, Rice FL, Reep RL. Mammalian tactile hair: divergence from a limited distribution. Ann N Y Acad Sci 2011; 1225:90-100. [DOI: 10.1111/j.1749-6632.2011.05979.x] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Endocrine function and neurobiology of the longest-living rodent, the naked mole-rat. Exp Gerontol 2011; 46:116-23. [DOI: 10.1016/j.exger.2010.09.005] [Citation(s) in RCA: 66] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2010] [Revised: 09/02/2010] [Accepted: 09/09/2010] [Indexed: 02/04/2023]
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Abstract
In recent years, considerable progress has been achieved in the comprehension of the profound effects of pheromones on reproductive physiology and behavior. Pheromones have been classified as molecules released by individuals and responsible for the elicitation of specific behavioral expressions in members of the same species. These signaling molecules, often chemically unrelated, are contained in body fluids like urine, sweat, specialized exocrine glands, and mucous secretions of genitals. The standard view of pheromone sensing was based on the assumption that most mammals have two separated olfactory systems with different functional roles: the main olfactory system for recognizing conventional odorant molecules and the vomeronasal system specifically dedicated to the detection of pheromones. However, recent studies have reexamined this traditional interpretation showing that both the main olfactory and the vomeronasal systems are actively involved in pheromonal communication. The current knowledge on the behavioral, physiological, and molecular aspects of pheromone detection in mammals is discussed in this review.
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Czech NU, Klauer G, Dehnhardt G, Siemers BM. Fringe for foraging? Histology of the bristle-like hairs on the tail membrane of the gleaning bat, Myotis nattereri. ACTA CHIROPTEROLOGICA 2008. [DOI: 10.3161/150811008x414872] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Towett PK, Kanui TI, Maloiy GMO, Juma F, Olongida Ole Miaron J. Activation of micro, delta or kappa opioid receptors by DAMGO, DPDPE, U-50488 or U-69593 respectively causes antinociception in the formalin test in the naked mole-rat (Heterocephalus glaber). Pharmacol Biochem Behav 2008; 91:566-72. [PMID: 18929596 DOI: 10.1016/j.pbb.2008.09.011] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/31/2008] [Revised: 09/18/2008] [Accepted: 09/23/2008] [Indexed: 10/21/2022]
Abstract
Data available on the role of the opioid systems of the naked mole-rat in nociception is scanty and unique compared to that of other rodents. In the current study, the effect of DAMGO, DPDPE and U-50488 and U-69593 on formalin-induced (20 microl, 10%) nociception were investigated. Nociceptive-like behaviors were quantified by scoring in blocks of 5 min the total amount of time (s) the animal spent scratching/biting the injected paw in the early (0-5 min) and in the late (25-60 min) phase of the test. In both the early and late phases, administration of 1 or 5 mg/kg of DAMGO or DPDPE caused a naloxone-attenuated decrease in the mean scratching/biting time. U-50488 and U-69593 at all the doses tested did not significantly change the mean scratching/biting time in the early phase. However, in the late phase U-50488 or U-69593 at the highest doses tested (1 or 5 mg/kg or 0.025 or 0.05 mg/kg, respectively) caused a statistically significant and naloxone-attenuated decrease in the mean scratching/biting time. The data showed that mu, delta or kappa-selective opioids causes antinociception in the formalin test in this rodent, adding novel information on the role of opioid systems of the animal on pain regulation.
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Affiliation(s)
- Philemon Kipkemoi Towett
- Neurophysiology and Neuropharmacology Research Laboratory, Department of Veterinary Anatomy, University of Nairobi, P.O. Box 00100-30197, Nairobi, Kenya.
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Water shrews detect movement, shape, and smell to find prey underwater. Proc Natl Acad Sci U S A 2008; 105:571-6. [PMID: 18184804 DOI: 10.1073/pnas.0709534104] [Citation(s) in RCA: 61] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
American water shrews (Sorex palustris) are aggressive predators that feed on a variety of terrestrial and aquatic prey. They often forage at night, diving into streams and ponds in search of food. We investigated how shrews locate submerged prey using high-speed videography, infrared lighting, and stimuli designed to mimic prey. Shrews attacked brief water movements, indicating motion is an important cue used to detect active or escaping prey. They also bit, retrieved, and attempted to eat model fish made of silicone in preference to other silicone objects showing that tactile cues are important in the absence of movement. In addition, water shrews preferentially sniffed model prey fish and crickets underwater by exhaling and reinhaling air through the nostrils, suggesting olfaction plays an important role in aquatic foraging. The possibility of echolocation, sonar, or electroreception was investigated by testing for ultrasonic and audible calls above and below water and by presenting electric fields to foraging shrews. We found no evidence for these abilities. We conclude that water shrews detect motion, shape, and smell to find prey underwater. The short latency of attacks to water movements suggests shrews may use a flush-pursuit strategy to capture some prey.
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A novel method of head fixation for the study of rodent facial function. Exp Neurol 2007; 205:279-82. [PMID: 17397835 DOI: 10.1016/j.expneurol.2007.02.014] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2006] [Revised: 01/25/2007] [Accepted: 02/18/2007] [Indexed: 11/18/2022]
Abstract
The rodent vibrissial system offers an excellent model for the study of both sensory and motor function. It has been widely employed to gather data pertaining to sensory and motor function involving the 5th and 7th cranial nerves and the central nervous system. Existing methods of head fixation for precise measurements of ocular and vibrissial function involve exposing the cranium and applying dental cement from which two or more threaded rods emerge. This common approach is suboptimal, requiring a relatively complicated implantation procedure, and results in a large, chronic interface between the scalp and environmentally exposed implant material attached to the skull. Here we describe a head fixation device that is inexpensive, easy to build, less prone to infection, preserves access to the cranial midline, and permits repeated measurements over many months.
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Smith TD, Bhatnagar KP, Dennis JC, Morrison EE, Park TJ. Growth-deficient vomeronasal organs in the naked mole-rat (Heterocephalus glaber). Brain Res 2006; 1132:78-83. [PMID: 17188655 DOI: 10.1016/j.brainres.2006.11.021] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2006] [Revised: 11/07/2006] [Accepted: 11/08/2006] [Indexed: 11/25/2022]
Abstract
The naked mole-rat (Heterocephalus glaber) is unusual in numerous life history characteristics as well as its eusocial organization. This species demonstrates widespread sexual suppression and prominent scent marking, behaviors that have been associated with pheromonal communication involving the vomeronasal organ in other rodents. Yet, previous studies indicate that urinary signals do not mediate sexual suppression in Heterocephalus. Surprisingly, no previous studies have examined the vomeronasal organ in this species. Here, we show that Heterocephalus is unique among rodents in showing no evidence of postnatal volumetric growth in the vomeronasal neuroepithelium. Subadults from birth to weaning fell within the same volume range as adults regardless of breeding/non-breeding status of the latter. A comparison of existing ontogenetic data on other mammals suggests that the proportionally small VNOs of Heterocephalus may be explained by a deficiency in VNNE growth. Growth deficiency of the vomeronasal organ in Heterocephalus may relate to a diminished role that pheromones play in certain social interactions for this species, such as breeding suppression. In light of the unique aspects of the vomeronasal organ in Heterocephalus, comparative studies of rodents may provide a model for understanding variation of this sensory system in other mammalian orders including primates, an order which shows a range from vestigial to demonstrably functional vomeronasal organs.
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Affiliation(s)
- Timothy D Smith
- School of Physical Therapy, Slippery Rock University, Slippery Rock, PA 16057, USA.
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Towett PK, Kanui TI, Juma FD. Stimulation of mu and delta opioid receptors induces hyperalgesia while stimulation of kappa receptors induces antinociception in the hot plate test in the naked mole-rat (Heterocephalus glaber). Brain Res Bull 2006; 71:60-8. [PMID: 17113929 DOI: 10.1016/j.brainresbull.2006.08.001] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2006] [Revised: 07/20/2006] [Accepted: 08/01/2006] [Indexed: 11/18/2022]
Abstract
The antinociceptive effects of highly selective mu (DAMGO), delta (DPDPE) and kappa (U-50488 and U-69593) opioid agonists were evaluated following intraperitoneal (i.p.) administration in the naked mole-rat. A hot plate test set at 60 degrees C was used as a nociceptive test and the latency to the stamping of the right hind paw (response latency) was used as the end-point. DAMGO (5-10 mg/kg) and DPDPE (2.5-5 mg/kg) caused a naloxone-reversible significant decrease in the mean response latency. Subcutaneous injection of naloxonazine (20 mg/kg) 24h prior to the administration of DAMGO (5 mg/kg) also blocked the reduction in the response latency observed when DAMGO was injected alone. On the contrary, U-50488 (2.5-5 mg/kg) or U-69593 (0.08 or 0.1 mg/kg) caused a naloxone-reversible significant increase in the mean response latency. These results showed that activation of mu or delta receptors caused hyperalgesia, whereas activation of kappa receptors caused antinociception in the hot plate test in naked mole-rat. This suggests that mu and delta receptors modulate thermal pain in a different way than kappa receptors in the naked mole-rat. It is not possible at the moment to point out how they modulate thermal pain as little is known about the neuropharmacology of the naked mole-rat.
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MESH Headings
- Analgesics, Opioid/pharmacology
- Animals
- Disease Models, Animal
- Female
- Hot Temperature/adverse effects
- Hyperalgesia/chemically induced
- Hyperalgesia/metabolism
- Hyperalgesia/physiopathology
- Male
- Mole Rats/metabolism
- Narcotic Antagonists/pharmacology
- Nerve Fibers, Unmyelinated/drug effects
- Nerve Fibers, Unmyelinated/metabolism
- Nociceptors/drug effects
- Nociceptors/metabolism
- Nociceptors/physiopathology
- Pain Measurement/methods
- Pain Threshold/drug effects
- Pain Threshold/physiology
- Reaction Time/drug effects
- Reaction Time/physiology
- Receptors, Opioid, delta/agonists
- Receptors, Opioid, delta/antagonists & inhibitors
- Receptors, Opioid, delta/metabolism
- Receptors, Opioid, kappa/agonists
- Receptors, Opioid, kappa/antagonists & inhibitors
- Receptors, Opioid, kappa/metabolism
- Receptors, Opioid, mu/agonists
- Receptors, Opioid, mu/antagonists & inhibitors
- Receptors, Opioid, mu/metabolism
- Skin/innervation
- Skin/physiopathology
- Thermosensing/drug effects
- Thermosensing/physiology
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Affiliation(s)
- Philemon Kipkemoi Towett
- Department of Veterinary Anatomy and Physiology, University of Nairobi, P.O. Box 30197, Nairobi, Kenya.
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Catania KC, Henry EC. Touching on somatosensory specializations in mammals. Curr Opin Neurobiol 2006; 16:467-73. [PMID: 16837185 DOI: 10.1016/j.conb.2006.06.010] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2006] [Revised: 06/20/2006] [Accepted: 06/30/2006] [Indexed: 10/24/2022]
Abstract
Specialized species often reveal general principles of brain organization and provide systems for analysis of sensory function. Subterranean species dependent on touch have particularly large somatosensory areas with modular cortical representations of sensory surfaces. Some species have added cortical areas to processing networks, have developed tactile foveas and have superior colliculi primarily devoted to somatosensation rather than vision. Recent studies reveal surprisingly large cortical representations of oral structures in primates and mole-rats. Cortical modules represent a range of different sensory surfaces in rodents, star-nosed moles and primates, indicating that similar developmental mechanisms operate in diverse species. Finally, manipulation of patterning genes in mice suggests evolutionary mechanisms for producing the specialized corticies of subterranean species.
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Affiliation(s)
- Kenneth C Catania
- Department of Biological Sciences, Vanderbilt University, Nashville, TN 37235, USA.
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Henry EC, Remple MS, O'Riain MJ, Catania KC. Organization of somatosensory cortical areas in the naked mole-rat (Heterocephalus glaber). J Comp Neurol 2006; 495:434-52. [PMID: 16485289 DOI: 10.1002/cne.20883] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Multiunit electrophysiology was combined with histological analysis of cortical sections to investigate the organization of somatosensory areas in the naked mole-rat. We provide new details for the organization of primary somatosensory cortex (S1) and identify cortical modules and barrels that correspond to the representations of different body parts. In addition, details of the location and organization of secondary somatosensory cortex (S2) are reported, and evidence for a third somatosensory representation, likely the parietal ventral area (PV), is provided and discussed. S1 contained a complete and systematic representation of the contralateral body surface and oral structures. The orientation of S1 was inverted, with the lower body represented medially and the face and oral structures located rostrolaterally. The S2 representation was found in caudolateral cortex forming a mirror image of S1. The two areas were joined at the representation of the vibrissae and snout, so that the orientation of S2 formed an upright representation of the body in cortex. Receptive fields for S2 were consistently larger than those in S1. Evidence for the presumptive parietal ventral area, lateral to S2, suggests that this area may be an inverted mirror image of S2. By aligning the electrophysiological maps of body representations with cytochrome oxidase-reacted cortical sections we were able to identify modules related to the buccal pad, chin, vibrissae, forelimb, hindlimb, trunk, tongue, lower incisor, and upper incisors. The orofacial modules in lateral cortex resemble similar modules reported to relate to oral structures previously described in the laboratory rat, owl monkey, and squirrel monkey.
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Affiliation(s)
- Erin C Henry
- Neuroscience Graduate Program, Vanderbilt University, Nashville, Tennessee 37235, USA
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Crish SD, Dengler-Crish CM, Catania KC. Central visual system of the naked mole-rat (Heterocephalus glaber). ACTA ACUST UNITED AC 2006; 288:205-12. [PMID: 16419086 DOI: 10.1002/ar.a.20288] [Citation(s) in RCA: 61] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Naked mole-rats are fossorial rodents native to eastern Africa that spend their lives in extensive subterranean burrows where visual cues are poor. Not surprisingly, they have a degenerated eye and optic nerve, suggesting they have poor visual abilities. However, little is known about their central visual system. To investigate the organization of their central visual system, we injected a neuronal tracer into the eyes of naked mole-rats and mice to compare the neural structures mediating vision. We found that the superior colliculus and lateral geniculate nucleus were severely atrophied in the naked mole-rat. The olivary pretectal nucleus was reduced but still retained its characteristic morphology, possibly indicating a role in light detection. In addition, the suprachiasmatic nucleus is well innervated and resembles the same structure in other rodents. The naked mole-rat appears to have selectively lost structures that mediate form vision while retaining structures needed for minimal entrainment of circadian rhythms. Similar results have been reported for other mole-rat species. Taken together, these data suggest that light detection may still play an important role in the lives of these "blind" animals: most likely for circadian entrainment or setting seasonal rhythms.
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Affiliation(s)
- Samuel D Crish
- Department of Biological Sciences and Neuroscience Program, Vanderbilt University, Nashville, Tennessee 37235, USA
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