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Krochmal AR, Roth TC. The case for investigating the cognitive map in nonavian reptiles. Anim Behav 2023. [DOI: 10.1016/j.anbehav.2023.01.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/11/2023]
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Mehlhorn J, Niski N, Liu K, Caspers S, Amunts K, Herold C. Regional Patterning of Adult Neurogenesis in the Homing Pigeon’s Brain. Front Psychol 2022; 13:889001. [PMID: 35898980 PMCID: PMC9311432 DOI: 10.3389/fpsyg.2022.889001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2022] [Accepted: 05/05/2022] [Indexed: 11/13/2022] Open
Abstract
In the avian brain, adult neurogenesis has been reported in the telencephalon of several species, but the functional significance of this trait is still ambiguous. Homing pigeons (Columba livia f.d.) are well-known for their navigational skills. Their brains are functionally adapted to homing with, e.g., larger hippocampi. So far, no comprehensive mapping of adult neuro- and gliogenesis or studies of different developmental neuronal stages in the telencephalon of homing pigeons exists, although comprehensive analyses in various species surely will result in a higher understanding of the functional significance of adult neurogenesis. Here, adult, free flying homing pigeons were treated with 5-bromo-deoxyuridine (BrdU) to label adult newborn cells. Brains were dissected and immunohistochemically processed with several markers (GFAP, Sox2, S100ß, Tbr2, DCX, Prox1, Ki67, NeuN, Calbindin, Calretinin) to study different stages of adult neurogenesis in a quantitative and qualitative way. Therefore, immature and adult newborn neurons and glial cells were analyzed along the anterior–posterior axis. The analysis proved the existence of different neuronal maturation stages and showed that immature cells, migrating neurons and adult newborn neurons and glia were widely and regionally unequally distributed. Double- and triple-labelling with developmental markers allowed a stage classification of adult neurogenesis in the pigeon brain (1: continuity of stem cells/proliferation, 2: fate specification, 3: differentiation/maturation, 4: integration). The most adult newborn neurons and glia were found in the intercalated hyperpallium (HI) and the hippocampal formation (HF). The highest numbers of immature (DCX+) cells were detected in the nidopallium (N). Generally, the number of newborn glial cells exceeded the number of newborn neurons. Individual structures (e.g., HI, N, and HF) showed further variations along the anterior–posterior axis. Our qualitative classification and the distribution of maturing cells in the forebrain support the idea that there is a functional specialization, respectively, that there is a link between brain-structure and function, species-specific requirements and adult neurogenesis. The high number of immature neurons also suggests a high level of plasticity, which points to the ability for rapid adaption to environmental changes through additive mechanisms. Furthermore, we discuss a possible influence of adult neurogenesis on spatial cognition.
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Affiliation(s)
- Julia Mehlhorn
- Institute for Anatomy I, Medical Faculty and University Hospital Düsseldorf, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
- *Correspondence: Julia Mehlhorn,
| | - Nelson Niski
- C. and O. Vogt-Institute for Brain Research, Medical Faculty and University Hospital Düsseldorf, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
| | - Ke Liu
- Institute for Anatomy I, Medical Faculty and University Hospital Düsseldorf, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
| | - Svenja Caspers
- Institute for Anatomy I, Medical Faculty and University Hospital Düsseldorf, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
- Institute of Neuroscience and Medicine (INM-1), Research Centre Jülich, Jülich, Germany
| | - Katrin Amunts
- C. and O. Vogt-Institute for Brain Research, Medical Faculty and University Hospital Düsseldorf, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
- Institute of Neuroscience and Medicine (INM-1), Research Centre Jülich, Jülich, Germany
| | - Christina Herold
- C. and O. Vogt-Institute for Brain Research, Medical Faculty and University Hospital Düsseldorf, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
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LaDage LD, Yu T, Zani PA. Higher Rate of Male Sexual Displays Correlates with Larger Ventral Posterior Amygdala Volume and Neuron Soma Volume in Wild-Caught Common Side-Blotched Lizards, Uta stansburiana. BRAIN, BEHAVIOR AND EVOLUTION 2022; 97:298-308. [PMID: 35537399 DOI: 10.1159/000524915] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/17/2021] [Accepted: 04/28/2022] [Indexed: 06/14/2023]
Abstract
Several areas of the vertebrate brain are involved in facilitating and inhibiting the production of sexual behaviors and displays. In the laboratory, a higher rate of sexual displays is correlated with a larger ventral posterior amygdala (VPA), an area of the brain involved in the expression of sexual display behaviors, as well as larger VPA neuronal somas. However, it remains unclear if individuals in the field reflect similar patterns, as there are likely many more selective pressures in the field that may also modulate the VPA architecture. In this study, we examined variation in VPA volume and neuron soma volume in wild-caught common side-blotched lizards (Uta stansburiana) from two different populations. In a population from Nevada, males experience high predation pressure and have decreased sexual display rates during the breeding season, whereas a population in Oregon has lower levels of predation and higher rates of male sexual displays. We found that wild-caught males from the population with lower display rates also exhibited decreased VPA volume and VPA neuron cell soma volume, which may suggest that decreased display rate, possibly due to increased predation rate, covaries with VPA attributes.
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Affiliation(s)
- Lara D LaDage
- Division of Mathematics & Natural Sciences, Penn State Altoona, Altoona, Pennsylvania, USA
| | - Tracy Yu
- Department of Biochemistry & Molecular Biology, The Pennsylvania State University, University Park, Pennsylvania, USA
| | - Peter A Zani
- Department of Biology, University of Wisconsin - Stevens Point, Stevens Point, Wisconsin, USA
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De Meester G, Baeckens S. Reinstating reptiles: from clueless creatures to esteemed models of cognitive biology. BEHAVIOUR 2021. [DOI: 10.1163/1568539x-00003718] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Abstract
Non-avian reptiles have long been neglect in cognitive science due to their reputation as slow and inflexible learners, but fortunately, this archaic view on reptile cognition is changing rapidly. The last two decades have witnessed a renewed interest in the cognitive capacities of reptiles, and more ecologically relevant protocols have been designed to measure such abilities. Now, we appreciate that reptiles possess an impressive set of cognitive skills, including problem-solving abilities, fast and flexible learning, quantity discrimination, and even social learning. This special issue highlights current research on reptiles in cognitive biology and showcases the diversity of research questions that can be answered by using reptiles as study model. Here, we briefly address (the key results of) the contributing articles and their role in the endeavour for total inclusion of reptiles in cognitive biological research, which is instrumental for our understanding of the evolution of animal cognition. We also discuss and illustrate the promising potential of reptiles as model organisms in various areas of cognitive research.
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Affiliation(s)
- Gilles De Meester
- Functional Morphology Lab, Biology Department, University of Antwerp, Belgium
| | - Simon Baeckens
- Functional Morphology Lab, Biology Department, University of Antwerp, Belgium
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Kverková K, Polonyiová A, Kubička L, Němec P. Individual and age-related variation of cellular brain composition in a squamate reptile. Biol Lett 2020; 16:20200280. [PMID: 32961085 DOI: 10.1098/rsbl.2020.0280] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Within-species variation in the number of neurons, other brain cells and their allocation to different brain parts is poorly studied. Here, we assess these numbers in a squamate reptile, the Madagascar ground gecko (Paroedura picta). We examined adults from two captive populations and three age groups within one population. Even though reptiles exhibit extensive adult neurogenesis, intrapopulation variation in the number of neurons is similar to that in mice. However, the two populations differed significantly in most measures, highlighting the fact that using only one population can underestimate within-species variation. There is a substantial increase in the number of neurons and decrease in neuronal density in adult geckos relative to hatchlings and an increase in the number of neurons in the telencephalon in fully grown adults relative to sexually mature young adults. This finding implies that adult neurogenesis does not only replace worn out but also adds new telencephalic neurons in reptiles during adulthood. This markedly contrasts with the situation in mammals, where the number of cortical neurons declines with age.
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Affiliation(s)
- Kristina Kverková
- Department of Zoology, Faculty of Science, Charles University, Viničná 7, CZ-128 44 Praha 2, Czech Republic
| | - Alexandra Polonyiová
- Department of Zoology, Faculty of Science, Charles University, Viničná 7, CZ-128 44 Praha 2, Czech Republic
| | - Lukáš Kubička
- Department of Ecology, Faculty of Science, Charles University, Viničná 7, CZ-128 44 Praha 2, Czech Republic
| | - Pavel Němec
- Department of Zoology, Faculty of Science, Charles University, Viničná 7, CZ-128 44 Praha 2, Czech Republic
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LaDage LD. Broadening the functional and evolutionary understanding of postnatal neurogenesis using reptilian models. ACTA ACUST UNITED AC 2020; 223:223/15/jeb210542. [PMID: 32788272 DOI: 10.1242/jeb.210542] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
The production of new neurons in the brains of adult animals was first identified by Altman and Das in 1965, but it was not until the late 20th century when methods for visualizing new neuron production improved that there was a dramatic increase in research on neurogenesis in the adult brain. We now know that adult neurogenesis is a ubiquitous process that occurs across a wide range of taxonomic groups. This process has largely been studied in mammals; however, there are notable differences between mammals and other taxonomic groups in how, why and where new neuron production occurs. This Review will begin by describing the processes of adult neurogenesis in reptiles and identifying the similarities and differences in these processes between reptiles and model rodent species. Further, this Review underscores the importance of appreciating how wild-caught animals vary in neurogenic properties compared with laboratory-reared animals and how this can be used to broaden the functional and evolutionary understanding of why and how new neurons are produced in the adult brain. Studying variation in neural processes across taxonomic groups provides an evolutionary context to adult neurogenesis while also advancing our overall understanding of neurogenesis and brain plasticity.
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Affiliation(s)
- Lara D LaDage
- Division of Mathematics and Natural Sciences, Penn State Altoona, 3000 Ivyside Dr., Altoona, PA 16601, USA
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Billings BK, Behroozi M, Helluy X, Bhagwandin A, Manger PR, Güntürkün O, Ströckens F. A three-dimensional digital atlas of the Nile crocodile (Crocodylus niloticus) forebrain. Brain Struct Funct 2020; 225:683-703. [PMID: 32009190 DOI: 10.1007/s00429-020-02028-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2019] [Accepted: 01/16/2020] [Indexed: 12/22/2022]
Abstract
The phylogenetic position of crocodilians in relation to birds and mammals makes them an interesting animal model for investigating the evolution of the nervous system in amniote vertebrates. A few neuroanatomical atlases are available for reptiles, but with a growing interest in these animals within the comparative neurosciences, a need for these anatomical reference templates is becoming apparent. With the advent of MRI being used more frequently in comparative neuroscience, the aim of this study was to create a three-dimensional MRI-based atlas of the Nile crocodile (Crocodylus niloticus) brain to provide a common reference template for the interpretation of the crocodilian, and more broadly reptilian, brain. Ex vivo MRI acquisitions in combination with histological data were used to delineate crocodilian brain areas at telencephalic, diencephalic, mesencephalic, and rhombencephalic levels. A total of 50 anatomical structures were successfully identified and outlined to create a 3-D model of the Nile crocodile brain. The majority of structures were more readily discerned within the forebrain of the crocodile with the methods used to produce this atlas. The anatomy outlined herein corresponds with both classical and recent crocodilian anatomical analyses, barring a few areas of contention predominantly related to a lack of functional data and conflicting nomenclature.
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Affiliation(s)
- Brendon K Billings
- Faculty of Health Sciences, School of Anatomical Sciences, University of the Witwatersrand, 7 York Road, Parktown, Johannesburg, 2193, South Africa
| | - Mehdi Behroozi
- Faculty of Psychology, Institute of Cognitive Neuroscience, Biopsychology, Ruhr-University Bochum, Universitätsstraße 150, 44780, Bochum, Germany
| | - Xavier Helluy
- Faculty of Psychology, Institute of Cognitive Neuroscience, Biopsychology, Ruhr-University Bochum, Universitätsstraße 150, 44780, Bochum, Germany
| | - Adhil Bhagwandin
- Faculty of Health Sciences, School of Anatomical Sciences, University of the Witwatersrand, 7 York Road, Parktown, Johannesburg, 2193, South Africa.,Faculty of Health Sciences, Department of Human Biology, Division of Clinical Anatomy and Biological Anthropology, University of Cape Town, Cape Town, South Africa
| | - Paul R Manger
- Faculty of Health Sciences, School of Anatomical Sciences, University of the Witwatersrand, 7 York Road, Parktown, Johannesburg, 2193, South Africa
| | - Onur Güntürkün
- Faculty of Psychology, Institute of Cognitive Neuroscience, Biopsychology, Ruhr-University Bochum, Universitätsstraße 150, 44780, Bochum, Germany
| | - Felix Ströckens
- Faculty of Psychology, Institute of Cognitive Neuroscience, Biopsychology, Ruhr-University Bochum, Universitätsstraße 150, 44780, Bochum, Germany.
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Roth TC, Krochmal AR, LaDage LD. Reptilian Cognition: A More Complex Picture via Integration of Neurological Mechanisms, Behavioral Constraints, and Evolutionary Context. Bioessays 2019; 41:e1900033. [PMID: 31210380 DOI: 10.1002/bies.201900033] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2019] [Revised: 05/10/2019] [Indexed: 12/16/2022]
Abstract
Unlike birds and mammals, reptiles are commonly thought to possess only the most rudimentary means of interacting with their environments, reflexively responding to sensory information to the near exclusion of higher cognitive function. However, reptilian brains, though structurally somewhat different from those of mammals and birds, use many of the same cellular and molecular processes to support complex behaviors in homologous brain regions. Here, the neurological mechanisms supporting reptilian cognition are reviewed, focusing specifically on spatial cognition and the hippocampus. These processes are compared to those seen in mammals and birds within an ecologically and evolutionarily relevant context. By viewing reptilian cognition through an integrative framework, a more robust understanding of reptile cognition is gleaned. Doing so yields a broader view of the evolutionarily conserved molecular and cellular mechanisms that underlie cognitive function and a better understanding of the factors that led to the evolution of complex cognition.
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Affiliation(s)
- Timothy C Roth
- Department of Psychology, Franklin and Marshall College, P.O. Box 3003, Lancaster, PA, 17603, USA
| | - Aaron R Krochmal
- Department of Biology, Washington College, 300 Washington Avenue, Chestertown, MD, 21620, USA
| | - Lara D LaDage
- Division of Mathematics and Natural Sciences, Penn State University Altoona, Altoona, PA, 16601, USA
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Augusto-Oliveira M, Arrifano GPF, Malva JO, Crespo-Lopez ME. Adult Hippocampal Neurogenesis in Different Taxonomic Groups: Possible Functional Similarities and Striking Controversies. Cells 2019; 8:cells8020125. [PMID: 30764477 PMCID: PMC6406791 DOI: 10.3390/cells8020125] [Citation(s) in RCA: 39] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2018] [Revised: 01/31/2019] [Accepted: 01/31/2019] [Indexed: 12/13/2022] Open
Abstract
Adult neurogenesis occurs in many species, from fish to mammals, with an apparent reduction in the number of both neurogenic zones and new neurons inserted into established circuits with increasing brain complexity. Although the absolute number of new neurons is high in some species, the ratio of these cells to those already existing in the circuit is low. Continuous replacement/addition plays a role in spatial navigation (migration) and other cognitive processes in birds and rodents, but none of the literature relates adult neurogenesis to spatial navigation and memory in primates and humans. Some models developed by computational neuroscience attribute a high weight to hippocampal adult neurogenesis in learning and memory processes, with greater relevance to pattern separation. In contrast to theories involving neurogenesis in cognitive processes, absence/rarity of neurogenesis in the hippocampus of primates and adult humans was recently suggested and is under intense debate. Although the learning process is supported by plasticity, the retention of memories requires a certain degree of consolidated circuitry structures, otherwise the consolidation process would be hampered. Here, we compare and discuss hippocampal adult neurogenesis in different species and the inherent paradoxical aspects.
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Affiliation(s)
- Marcus Augusto-Oliveira
- Laboratory of Molecular Pharmacology, Institute of Biological Sciences, Federal University of Pará, Belém 66075-110, Brazil.
- Laboratory of Research on Neurodegeneration and Infection, University Hospital João de Barros Barreto, Federal University of Pará, Belém 66073-005, Brazil.
- Laboratory of Experimental Neuropathology, Department of Pharmacology, University of Oxford, Oxford OX1 3QT, UK.
| | - Gabriela P F Arrifano
- Laboratory of Molecular Pharmacology, Institute of Biological Sciences, Federal University of Pará, Belém 66075-110, Brazil.
- Laboratory of Experimental Neuropathology, Department of Pharmacology, University of Oxford, Oxford OX1 3QT, UK.
| | - João O Malva
- Coimbra Institute for Clinical and Biomedical Research (iCBR), and Center for Neuroscience and Cell Biology and Institute for Biomedical Imaging and Life Sciences (CNC.IBILI), Faculty of Medicine, University of Coimbra, Coimbra 3000-548, Portugal.
| | - Maria Elena Crespo-Lopez
- Laboratory of Molecular Pharmacology, Institute of Biological Sciences, Federal University of Pará, Belém 66075-110, Brazil.
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Lutterschmidt DI, Lucas AR, Karam RA, Nguyen VT, Rasmussen MR. Sexually Dimorphic Patterns of Cell Proliferation in the Brain Are Linked to Seasonal Life-History Transitions in Red-Sided Garter Snakes. Front Neurosci 2018; 12:364. [PMID: 29910707 PMCID: PMC5992280 DOI: 10.3389/fnins.2018.00364] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2017] [Accepted: 05/09/2018] [Indexed: 01/17/2023] Open
Abstract
Seasonal rhythms in physiology and behavior are widespread across diverse taxonomic groups and may be mediated by seasonal changes in neurogenesis, including cell proliferation, migration, and differentiation. We examined if cell proliferation in the brain is associated with the seasonal life-history transition from spring breeding to migration and summer foraging in a free-ranging population of red-sided garter snakes (Thamnophis sirtalis) in Manitoba, Canada. We used the thymidine analog 5-bromo-2′-deoxyuridine (BrdU) to label newly proliferated cells within the brain of adult snakes collected from the den during the mating season or from a road located along their migratory route. To assess rates of cell migration, we further categorized BrdU-labeled cells according to their location within the ventricular zone or parenchymal region of the nucleus sphericus (homolog of the amygdala), preoptic area/hypothalamus, septal nucleus, and cortex (homolog of the hippocampus). We found that cell proliferation and cell migration varied significantly with sex, the migratory status of snakes, and reproductive behavior in males. In most regions of interest, patterns of cell proliferation were sexually dimorphic, with males having significantly more BrdU-labeled cells than females prior to migration. However, during the initial stages of migration, females exhibited a significant increase in cell proliferation within the nucleus sphericus, hypothalamus, and septal nucleus, but not in any subregion of the cortex. In contrast, migrating males exhibited a significant increase in cell proliferation within the medial cortex but no other brain region. Because it is unlikely that the medial cortex plays a sexually dimorphic role in spatial memory during spring migration, we speculate that cell proliferation within the male medial cortex is associated with regulation of the hypothalamus-pituitary-adrenal axis. Finally, the only brain region where cell migration into the parenchymal region varied significantly with sex or migratory status was the hypothalamus. These results suggest that the migration of newly proliferated cells and/or the continued division of undifferentiated cells are activated earlier or to a greater extent in the hypothalamus. Our data suggest that sexually dimorphic changes in cell proliferation and cell migration in the adult brain may mediate sex differences in the timing of seasonal life-history transitions.
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Affiliation(s)
| | - Ashley R Lucas
- Department of Biology, Portland State University, Portland, OR, United States
| | - Ritta A Karam
- Department of Biology, Portland State University, Portland, OR, United States
| | - Vicky T Nguyen
- Department of Biology, Portland State University, Portland, OR, United States
| | - Meghann R Rasmussen
- Department of Biology, Portland State University, Portland, OR, United States
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LaDage LD, Roth TC, Downs CJ, Sinervo B, Pravosudov VV. Increased Testosterone Decreases Medial Cortical Volume and Neurogenesis in Territorial Side-Blotched Lizards ( Uta stansburiana). Front Neurosci 2017; 11:97. [PMID: 28298883 PMCID: PMC5331184 DOI: 10.3389/fnins.2017.00097] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2017] [Accepted: 02/14/2017] [Indexed: 01/18/2023] Open
Abstract
Variation in an animal's spatial environment can induce variation in the hippocampus, an area of the brain involved in spatial cognitive processing. Specifically, increased spatial area use is correlated with increased hippocampal attributes, such as volume and neurogenesis. In the side-blotched lizard (Uta stansburiana), males demonstrate alternative reproductive tactics and are either territorial—defending large, clearly defined spatial boundaries—or non-territorial—traversing home ranges that are smaller than the territorial males' territories. Our previous work demonstrated cortical volume (reptilian hippocampal homolog) correlates with these spatial niches. We found that territorial holders have larger medial cortices than non-territory holders, yet these differences in the neural architecture demonstrated some degree of plasticity as well. Although we have demonstrated a link among territoriality, spatial use, and brain plasticity, the mechanisms that underlie this relationship are unclear. Previous studies found that higher testosterone levels can induce increased use of the spatial area and can cause an upregulation in hippocampal attributes. Thus, testosterone may be the mechanistic link between spatial area use and the brain. What remains unclear, however, is if testosterone can affect the cortices independent of spatial experiences and whether testosterone differentially interacts with territorial status to produce the resultant cortical phenotype. In this study, we compared neurogenesis as measured by the total number of doublecortin-positive cells and cortical volume between territorial and non-territorial males supplemented with testosterone. We found no significant differences in the number of doublecortin-positive cells or cortical volume among control territorial, control non-territorial, and testosterone-supplemented non-territorial males, while testosterone-supplemented territorial males had smaller medial cortices containing fewer doublecortin-positive cells. These results demonstrate that testosterone can modulate medial cortical attributes outside of differential spatial processing experiences but that territorial males appear to be more sensitive to alterations in testosterone levels compared with non-territorial males.
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Affiliation(s)
- Lara D LaDage
- Division of Mathematics and Natural Sciences, Penn State University Altoona Altoona, PA, USA
| | - Timothy C Roth
- Department of Psychology, Franklin and Marshall College Lancaster, PA, USA
| | | | - Barry Sinervo
- Department of Ecology and Evolutionary Biology, University of California Santa Cruz, CA, USA
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Yang C, Wang L, Xing X, Gao Y, Guo L. Seasonal variation in telencephalon cell proliferation in adult female tsinling dwarf skinks (Scincella tsinlingensis). Brain Res 2017; 1662:7-15. [PMID: 28237546 DOI: 10.1016/j.brainres.2017.02.015] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2016] [Revised: 02/08/2017] [Accepted: 02/14/2017] [Indexed: 11/25/2022]
Abstract
In adult mammals, neurogenesis is limited to specific niches in the brain, but considerable adult neurogenesis occurs in many brain regions in non-mammalian vertebrates. Non-mammalian vertebrates provide invaluable comparative material for understanding the core mechanisms of adult neural stem cell maintenance and fate, but phylogenetic differences in adult neurogenesis remain poorly understood. Here we examine cell proliferation seasonality in the telencephalon of adult female tsinling dwarf skinks (Scincella tsinlingensis) by injecting wild animals caught in summer, autumn and spring, and animals caught in autumn and raised under winter conditions, with 5-Bromo-2'-deoxyuridine (BrdU). Then, 24h, 7d and 28d after BrdU administration we examined brain tissue and quantified BrdU-labeled cells as a marker of neuronal proliferation. The highest number of labeled cells in the telencephalon was found in the 7d group. BrdU-positive cells were widely distributed in the anterior olfactory nucleus (AON), medial cortex (MC), dorsal cortex (DC), lateral cortex (LC), dorsal ventricular ridge (DVR), septum (SP), striatum (STR) and nucleus sphericus (NS). No BrdU-positive cells were detected in olfactory bulbs or elsewhere in the telencephalon. The highest proliferative levels were found in the AON in autumn. The NS exhibited relatively high levels of cell proliferation. The proliferative rate in the AON fluctuated seasonally as autumn>summer>spring>winter. Glial fibrillary acidic protein-positive cells were widely distributed in the telencephalon and their fibrous processes extended into brain parenchyma and anchored in the meninges. Doublecortin-positive newborn neurons of the subventricular zone appeared to migrate into the cerebral cortex via the radial migratory stream. Cell proliferation in the telencephalon of adult female S. tsinlingensis fluctuates seasonally, especially in regions related to olfactory memory. This is the first demonstration of proliferative activity in the telencephalon of a skink.
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Affiliation(s)
- Chun Yang
- School of Life Sciences, Shanxi Normal University, Linfen, Shanxi 041000, China.
| | - Limin Wang
- School of Life Sciences, Shanxi Normal University, Linfen, Shanxi 041000, China
| | - Xiangyang Xing
- School of Life Sciences, Shanxi Normal University, Linfen, Shanxi 041000, China
| | - Yanyan Gao
- School of Life Sciences, Shanxi Normal University, Linfen, Shanxi 041000, China
| | - Li Guo
- School of Life Sciences, Shanxi Normal University, Linfen, Shanxi 041000, China
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Powers AS. Preface. BRAIN, BEHAVIOR AND EVOLUTION 2016; 87:143-145. [PMID: 27560929 DOI: 10.1159/000447046] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
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