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Blixhavn CH, Haug FMŠ, Kleven H, Puchades MA, Bjaalie JG, Leergaard TB. A Timm-Nissl multiplane microscopic atlas of rat brain zincergic terminal fields and metal-containing glia. Sci Data 2023; 10:150. [PMID: 36944675 PMCID: PMC10030855 DOI: 10.1038/s41597-023-02012-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2022] [Accepted: 02/09/2023] [Indexed: 03/23/2023] Open
Abstract
The ability of Timm's sulphide silver method to stain zincergic terminal fields has made it a useful neuromorphological marker. Beyond its roles in zinc-signalling and neuromodulation, zinc is involved in the pathophysiology of ischemic stroke, epilepsy, degenerative diseases and neuropsychiatric conditions. In addition to visualising zincergic terminal fields, the method also labels transition metals in neuronal perikarya and glial cells. To provide a benchmark reference for planning and interpretation of experimental investigations of zinc-related phenomena in rat brains, we have established a comprehensive repository of serial microscopic images from a historical collection of coronally, horizontally and sagittally oriented rat brain sections stained with Timm's method. Adjacent Nissl-stained sections showing cytoarchitecture, and customised atlas overlays from a three-dimensional rat brain reference atlas registered to each section image are included for spatial reference and guiding identification of anatomical boundaries. The Timm-Nissl atlas, available from EBRAINS, enables experimental researchers to navigate normal rat brain material in three planes and investigate the spatial distribution and density of zincergic terminal fields across the entire brain.
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Affiliation(s)
- Camilla H Blixhavn
- Department of Molecular Medicine, Institute of Basic Medical Sciences, University of Oslo, Oslo, Norway
| | - Finn-Mogens Š Haug
- Department of Molecular Medicine, Institute of Basic Medical Sciences, University of Oslo, Oslo, Norway
| | - Heidi Kleven
- Department of Molecular Medicine, Institute of Basic Medical Sciences, University of Oslo, Oslo, Norway
| | - Maja A Puchades
- Department of Molecular Medicine, Institute of Basic Medical Sciences, University of Oslo, Oslo, Norway
| | - Jan G Bjaalie
- Department of Molecular Medicine, Institute of Basic Medical Sciences, University of Oslo, Oslo, Norway
| | - Trygve B Leergaard
- Department of Molecular Medicine, Institute of Basic Medical Sciences, University of Oslo, Oslo, Norway.
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Fujita H, Imura K, Takiguchi M, Funakoshi K. Postnatal development of thalamic reticular nucleus projections to the anterior thalamic nuclei in rats. Eur J Histochem 2022; 66:3370. [PMID: 35330554 PMCID: PMC8992380 DOI: 10.4081/ejh.2022.3370] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2021] [Accepted: 02/26/2022] [Indexed: 11/22/2022] Open
Abstract
The thalamic reticular nucleus (TRN) projects inhibitory signals to the thalamus, thereby controlling thalamocortical connections. Few studies have examined the development of TRN projections to the anterior thalamic nuclei with regard to axon course and the axon terminal distributions. In the present study, we used parvalbumin (PV) immunostaining to investigate inhibitory projections from the TRN to the thalamus in postnatal (P) 2- to 5-week-old rats (P14-35). The distribution of PV-positive (+) nerve fibers and nerve terminals markedly differed among the anterior thalamic nuclei at P14. Small, beaded nerve terminals were more distributed throughout the anterodorsal nucleus (AD) than in the anteroventral nucleus (AV) and anteromedial nucleus (AM). PV+ fibers traveling from the TRN to the AD were observed in the AV and AM. Nodular nerve terminals, spindle or en passant terminals, were identified on the axons passing through the AV and AM. At P21, axon bundles traveling without nodular terminals were observed, and nerve terminals were distributed throughout the AV and AM similar to the AD. At P28 and P35, the nerve terminals were evenly distributed throughout each nucleus. In addition, DiI tracer injections into the retrosplenial cortex revealed retrogradely-labeled projection neurons in the 3 nuclei at P14. At P14, the AD received abundant projections from the TRN and then projected to the retrosplenial cortex. The AV and AM seem to receive projections with distinct nodular nerve terminals from the TRN and project to the retrosplenial cortex. The projections from TRN to the AV and AM with nodular nerve terminals at P14 are probably developmental-period specific. In comparison, the TRN projections to the AD at P14 might be related to the development of spatial navigation as part of the head orientation system.
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Affiliation(s)
- Hitoshi Fujita
- Department of Neuroanatomy, Graduate School of Medicine, Yokohama City University, Yokohama.
| | - Kosuke Imura
- Department of Neuroanatomy, Graduate School of Medicine, Yokohama City University, Yokohama.
| | - Masahito Takiguchi
- Department of Neuroanatomy, Graduate School of Medicine, Yokohama City University, Yokohama.
| | - Kengo Funakoshi
- Department of Neuroanatomy, Graduate School of Medicine, Yokohama City University, Yokohama.
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Viale B, Song L, Petrenko V, Wenger Combremont AL, Contestabile A, Bocchi R, Salmon P, Carleton A, An L, Vutskits L, Kiss JZ. Transient Deregulation of Canonical Wnt Signaling in Developing Pyramidal Neurons Leads to Dendritic Defects and Impaired Behavior. Cell Rep 2020; 27:1487-1502.e6. [PMID: 31042475 DOI: 10.1016/j.celrep.2019.04.026] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2018] [Revised: 02/28/2019] [Accepted: 04/03/2019] [Indexed: 12/30/2022] Open
Abstract
During development, the precise implementation of molecular programs is a key determinant of proper dendritic development. Here, we demonstrate that canonical Wnt signaling is active in dendritic bundle-forming layer II pyramidal neurons of the rat retrosplenial cortex during dendritic branching and spine formation. Transient downregulation of canonical Wnt transcriptional activity during the early postnatal period irreversibly reduces dendritic arbor architecture, leading to long-lasting deficits in spatial exploration and/or navigation and spatial memory in the adult. During the late phase of dendritogenesis, canonical Wnt-dependent transcription regulates spine formation and maturation. We identify neurotrophin-3 as canonical Wnt target gene in regulating dendritogenesis. Our findings demonstrate how temporary imbalance in canonical Wnt signaling during specific time windows can result in irreversible dendritic defects, leading to abnormal behavior in the adult.
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Affiliation(s)
- Beatrice Viale
- Department of Basic Neurosciences, University of Geneva Medical School, 1211 Geneva 4, Switzerland
| | - Lin Song
- Department of Basic Neurosciences, University of Geneva Medical School, 1211 Geneva 4, Switzerland; School of Life Science and Biotechnology, Dalian University of Technology, Dalian, Liaoning 116024, China
| | - Volodymyr Petrenko
- Department of Basic Neurosciences, University of Geneva Medical School, 1211 Geneva 4, Switzerland
| | | | - Alessandro Contestabile
- Department of Basic Neurosciences, University of Geneva Medical School, 1211 Geneva 4, Switzerland
| | - Riccardo Bocchi
- Department of Basic Neurosciences, University of Geneva Medical School, 1211 Geneva 4, Switzerland
| | - Patrick Salmon
- Department of Basic Neurosciences, University of Geneva Medical School, 1211 Geneva 4, Switzerland
| | - Alan Carleton
- Department of Basic Neurosciences, University of Geneva Medical School, 1211 Geneva 4, Switzerland
| | - Lijia An
- School of Life Science and Biotechnology, Dalian University of Technology, Dalian, Liaoning 116024, China
| | - Laszlo Vutskits
- Department of Basic Neurosciences, University of Geneva Medical School, 1211 Geneva 4, Switzerland; Department of Anesthesiology, Pharmacology and Intensive Care, University Hospitals of Geneva, 1211 Geneva 4, Switzerland
| | - Jozsef Zoltan Kiss
- Department of Basic Neurosciences, University of Geneva Medical School, 1211 Geneva 4, Switzerland.
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Khalil R, Levitt JB. Use of Synaptic Zinc Histochemistry to Reveal Different Regions and Laminae in the Developing and Adult Brain. J Vis Exp 2017. [PMID: 29155788 DOI: 10.3791/56547] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022] Open
Abstract
Characterization of anatomical and functional brain organization and development requires accurate identification of distinct neural circuits and regions in the immature and adult brain. Here we describe a zinc histochemical staining procedure that reveals differences in staining patterns among different layers and brain regions. Others have utilized this procedure not only to reveal the distribution of zinc-containing neurons and circuits in the brain, but also to successfully delineate areal and laminar boundaries in the developing and adult brain in several species. Here we illustrate this staining procedure with images from developing and adult ferret brains. We reveal a zinc-staining pattern that serves as an anatomical marker of areas and layers, and can be reliably used to distinguish visual cortical areas in the developing and adult visual cortex. The main goal of this protocol is to present a histochemical method that allows the accurate identification of layers and regions in the developing and adult brain where other methods fail to do so. Secondarily, in conjunction with densitometric image analysis, this method allows one to assess the distribution of synaptic zinc to reveal potential changes throughout development. This protocol describes in detail the reagents, tools, and steps necessary to successively stain frozen brain sections. Although this protocol is described using ferret brain tissue, it can easily be adapted for use in rodents, cats, or monkeys as well as in other brain regions.
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Affiliation(s)
- Reem Khalil
- Department of Biology, Chemistry and Environmental Sciences, American University of Sharjah;
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McAllister BB, Dyck RH. Zinc transporter 3 (ZnT3) and vesicular zinc in central nervous system function. Neurosci Biobehav Rev 2017. [DOI: 10.1016/j.neubiorev.2017.06.006] [Citation(s) in RCA: 97] [Impact Index Per Article: 13.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
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6
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Oda S, Funato H, Sato F, Adachi-Akahane S, Ito M, Takase K, Kuroda M. A subset of thalamocortical projections to the retrosplenial cortex possesses two vesicular glutamate transporter isoforms, VGluT1 and VGluT2, in axon terminals and somata. J Comp Neurol 2015; 522:2089-106. [PMID: 24639017 DOI: 10.1002/cne.23519] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2013] [Revised: 11/21/2013] [Accepted: 12/04/2013] [Indexed: 01/14/2023]
Abstract
Vesicular glutamate transporter isoforms, VGluT1-VGluT3, accumulate glutamate into synaptic vesicles and are considered to be important molecules in glutamatergic transmission. Among them, VGluT2 mRNA is expressed predominantly throughout the dorsal thalamus, whereas VGluT1 mRNA is expressed in a few thalamic nuclei. In the thalamic nuclei that project to the retrosplenial cortex (RSC), VGluT1 mRNA is expressed strongly in the anterodorsal thalamic nucleus (AD), is expressed moderately in the anteroventral and laterodorsal thalamic nuclei, and is not expressed in the anteromedial thalamic nucleus. Thus, it has been strongly suggested that a subset of thalamocortical projections to RSC possesses both VGluT1 and VGluT2. In this study, double-labeled neuronal somata showing both VGluT1 and VGluT2 immunolabelings were found exclusively in the ventral region of AD (vAD). Many double-labeled axon terminals were also found in two major targets of vAD, the rostral part of the reticular thalamic nucleus and layers Ia and III-IV of the retrosplenial granular b cortex (RSGb). Some were also found in layer Ia of the retrosplenial granular a cortex (RSGa). These axon terminals contain significant amounts of both VGluTs. Because the subset of thalamocortical projections to RSC has a unique molecular basis in the glutamatergic transmission system, it might play an important role in the higher cognitive functions processed in the RSC. Furthermore, double-labeled axon terminals of a different type were distributed in RSGb and RSGa. Because they are small and the immunoreactivity of VGluT2 is significantly weaker than that of VGluT1, they seemed to be a subset of corticocortical terminals.
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Affiliation(s)
- Satoko Oda
- Department of Anatomy, School of Medicine, Toho University, Tokyo, 143-8540, Japan
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Ma J, Yao XH, Fu Y, Yu YC. Development of Layer 1 Neurons in the Mouse Neocortex. Cereb Cortex 2014; 24:2604-18. [DOI: 10.1093/cercor/bht114] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
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Abstract
Knowledge of thalamocortical (TC) processing comes mainly from studying core thalamic systems that project to middle layers of primary sensory cortices. However, most thalamic relay neurons comprise a matrix of cells that are densest in the "nonspecific" thalamic nuclei and usually target layer 1 (L1) of multiple cortical areas. A longstanding hypothesis is that matrix TC systems are crucial for regulating neocortical excitability during changing behavioral states, yet we know almost nothing about the mechanisms of such regulation. It is also unclear whether synaptic and circuit mechanisms that are well established for core sensory TC systems apply to matrix TC systems. Here we describe studies of thalamic matrix influences on mouse prefrontal cortex using optogenetic and in vitro electrophysiology techniques. Channelrhodopsin-2 was expressed in midline and paralaminar (matrix) thalamic neurons, and their L1-projecting TC axons were activated optically. Contrary to conventional views, we found that matrix TC projections to L1 could transmit relatively strong, fast, high-fidelity synaptic signals. L1 TC projections preferentially drove inhibitory interneurons of L1, especially those of the late-spiking subtype, and often triggered feedforward inhibition in both L1 interneurons and pyramidal cells of L2/L3. Responses during repetitive stimulation were far more sustained for matrix than for core sensory TC pathways. Thus, matrix TC circuits appear to be specialized for robust transmission over relatively extended periods, consistent with the sort of persistent activation observed during working memory and potentially applicable to state-dependent regulation of excitability.
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Ichinohe N. Small-scale module of the rat granular retrosplenial cortex: an example of the minicolumn-like structure of the cerebral cortex. Front Neuroanat 2012; 5:69. [PMID: 22275884 PMCID: PMC3254062 DOI: 10.3389/fnana.2011.00069] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2011] [Accepted: 12/28/2011] [Indexed: 11/23/2022] Open
Abstract
Structures associated with the small-scale module called “minicolumn” can be observed frequently in the cerebral cortex. However, the description of functional characteristics remains obscure. A significant confounding factor is the marked variability both in the definition of a minicolumn and in the diagnostic markers for identifying a minicolumn (see for review, Jones, 2000; DeFelipe et al., 2002; Rockland and Ichinohe, 2004). Within a minicolumn, cell columns are easily visualized by conventional Nissl staining. Dendritic bundles were first discovered with Golgi methods, but are more easily seen with microtubule-associated protein 2 immunohistochemistry. Myelinated axon bundles can be seen by Tau immunohistochemistry or myelin staining. Axon bundles of double bouquet cell can be seen by calbindin immunohistochemistry. The spatial interrelationship among these morphological elements is more complex than expected and is neither clear nor unanimously agreed upon. In this review, I would like to focus first on the minicolumnar structure found in layers 1 and 2 of the rat granular retrosplenial cortex. This modular structure was first discovered as a combination of prominent apical dendritic bundles from layer 2 pyramidal neurons and spatially matched thalamocortical patchy inputs (Wyss et al., 1990). Further examination showed more intricate components of this modular structure, which will be reviewed in this paper. Second, the postnatal development of this structure and potential molecular players for its formation will be reviewed. Thirdly, I will discuss how this modular organization is transformed in mutant rodents with a disorganized layer structure in the cerebral cortex (i.e., reeler mouse and shaking rat Kawasaki). Lastly, the potential significance of this type of module will be discussed.
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Affiliation(s)
- Noritaka Ichinohe
- Department of Ultrastructural Research, National Institute of Neuroscience, National Center of Neurology and Psychiatry Kodaira, Tokyo, Japan
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Zgraggen E, Boitard M, Roman I, Kanemitsu M, Potter G, Salmon P, Vutskits L, Dayer AG, Kiss JZ. Early postnatal migration and development of layer II pyramidal neurons in the rodent cingulate/retrosplenial cortex. Cereb Cortex 2012; 22:144-57. [PMID: 21625013 DOI: 10.1093/cercor/bhr097] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2023] Open
Abstract
The cingulate and retrosplenial regions are major components of the dorsomedial (dm) limbic cortex and have been implicated in a range of cognitive functions such as emotion, attention, and spatial memory. While the structure and connectivity of these cortices are well characterized, little is known about their development. Notably, the timing and mode of migration that govern the appropriate positioning of late-born neurons remain unknown. Here, we analyzed migratory events during the early postnatal period from ventricular/subventricular zone (VZ/SVZ) to the cerebral cortex by transducing neuronal precursors in the VZ/SVZ of newborn rats/mice with Tomato/green fluorescent protein-encoding lentivectors. We have identified a pool of postmitotic pyramidal precursors in the dm part of the neonatal VZ/SVZ that migrate into the medial limbic cortex during the first postnatal week. Time-lapse imaging demonstrates that these cells migrate on radial glial fibers by locomotion and display morphological and behavioral changes as they travel through the white matter and enter into the cortical gray matter. In the granular retrosplenial cortex, these cells give rise to a Satb2+ pyramidal subtype and develop dendritic bundles in layer I. Our observations provide the first insight into the patterns and dynamics of cell migration into the medial limbic cortex.
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Affiliation(s)
- Eloisa Zgraggen
- Department of Neurosciences, University of Geneva Medical School, CH-1211 Geneva 4, Switzerland
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Cheng XR, Yang Y, Zhou WX, Zhang YX. Expression of VGLUTs contributes to degeneration and acquisition of learning and memory. Neurobiol Learn Mem 2011; 95:361-75. [PMID: 21295146 DOI: 10.1016/j.nlm.2011.01.010] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2010] [Revised: 01/16/2011] [Accepted: 01/25/2011] [Indexed: 12/27/2022]
Abstract
Vesicular glutamate transporters (VGLUTs), which include VGLUT1, VGLUT2 and VGLUT3, are responsible for the uploading of L-glutamate into synaptic vesicles. The expression pattern of VGLUTs determines the level of synaptic vesicle filling (i.e., glutamate quantal size) and directly influences glutamate receptors and glutamatergic synaptic transmission; thus, VGLUTs may play a key role in learning and memory in the central nervous system. To determine whether VGLUTs contribute to the degeneration or acquisition of learning and memory, we used an animal model for the age-related impairment of learning and memory, senescence-accelerated mouse/prone 8 (SAMP8). KM mice were divided into groups based on their learning and memory performance in a shuttle-box test. The expression of VGLUTs and synaptophysin (Syp) mRNA and protein in the cerebral cortex and hippocampus were investigated with real-time fluorescence quantitative PCR and western blot, respectively. Our results demonstrate that, in the cerebral cortex, protein expression of VGLUT1, VGLUT2, VGLUT3 and Syp was decreased in SAMP8 with age and increased in KM mice, which displayed an enhanced capacity for learning and memory. The protein expression of VGLUT2 and Syp was decreased in the hippocampus of SAMP8 with aging. The expression level of VGLUT1 and VGLUT2 proteins were highest in KM mouse group with a 76-100% avoidance score in the shuttle-box test. These data demonstrate that protein expression of VGLUT1, VGLUT2 and Syp decreases age-dependently in SAMP8 and increases in a learning- and memory-dependent manner in KM mice. Correlation analysis indicated the protein expression of VGLUT1, VGLUT2 and Syp has a positive correlation with the capacity of learning and memory.
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Affiliation(s)
- Xiao-Rui Cheng
- Beijing Institute of Pharmacology and Toxicology, Beijing 100850, China
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de Olmos S, Bender C, de Olmos JS, Lorenzo A. Neurodegeneration and prolonged immediate early gene expression throughout cortical areas of the rat brain following acute administration of dizocilpine. Neuroscience 2009; 164:1347-59. [PMID: 19772897 DOI: 10.1016/j.neuroscience.2009.09.022] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2009] [Accepted: 09/13/2009] [Indexed: 10/20/2022]
Abstract
N-methyl-d-aspartate receptor antagonist drugs (NMDA-A), such as dizocilpine (MK801), induce long-lasting behavioral disturbances reminiscent to psychotic disorders in humans. To identify cortical structures affected by NMDA-A, we used a single dose of MK801 (10 mg/kg) that caused low and high neurodegeneration in intact and orchiectomized male rats, respectively. Degenerating somas (neuronal death) and axonal/synaptic endings (terminal degeneration) were depicted by a silver technique, and functionally affected cortical neuronal subpopulations by Egr-1, c-Fos, and FosB/DeltaFosB-immunolabeling. In intact males, MK801 triggered a c-Fos induction that remained high for more than 24 h in selected layers of the retrosplenial, somatosensory and entorhinal cortices. MK801-induced neurodegeneration reached its peak at 72 h. Degenerating somas were restricted to layer IV of the granular subdivision of the retrosplenial cortex, and were accompanied by suppression of Egr-1 immunolabeling. Terminal degeneration extended to selected layers of the retrosplenial, somatosensory and parahippocampal cortices, which are target areas of retrosplenial cortex. Induction of FosB/DeltaFosB by MK801 also extended to the same cortical layers affected by terminal degeneration, likely reflecting the damage of synaptic connectivity. In orchiectomized males, the neurodegenerative and functional effects of MK801 were exacerbated. Degenerative somas in layer IV of the retrosplenial cortex significantly increased, with a parallel enhancement of terminal degeneration and FosB/DeltaFosB-expression in the mentioned cortical structures, but no additional areas were affected. These observations reveal that synaptic dysfunction/degeneration in the retrosplenial, somatosensory and parahippocampal cortices might underlie the long-lasting impairments induced by NMDA-A.
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Affiliation(s)
- S de Olmos
- Instituto de Investigación Médica Mercedes y Martín Ferreyra (INIMEC-CONICET), Friuli 2434, 5016-Córdoba, Argentina
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Wong P, Kaas JH. Architectonic subdivisions of neocortex in the gray squirrel (Sciurus carolinensis). Anat Rec (Hoboken) 2008; 291:1301-33. [PMID: 18780299 PMCID: PMC2908424 DOI: 10.1002/ar.20758] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Squirrels are highly visual mammals with an expanded cortical visual system and a number of well-differentiated architectonic fields. To describe and delimit cortical fields, subdivisions of cortex were reconstructed from serial brain sections cut in the coronal, sagittal, or horizontal planes. Architectonic characteristics of cortical areas were visualized after brain sections were processed with immunohistochemical and histochemical procedures for revealing parvalbumin, calbindin, neurofilament protein, vesicle glutamate transporter 2, limbic-associated membrane protein, synaptic zinc, cytochrome oxidase, myelin or Nissl substance. In general, these different procedures revealed similar boundaries between areas, suggesting that functionally relevant borders were being detected. The results allowed a more precise demarcation of previously identified areas as well as the identification of areas that had not been previously described. Primary sensory cortical areas were characterized by sparse zinc staining of layer 4, as thalamocortical terminations lack zinc, as well as by layer 4 terminations rich in parvalbumin and vesicle glutamate transporter 2. Primary areas also expressed higher levels of cytochrome oxidase and myelin. Primary motor cortex was associated with large SMI-32 labeled pyramidal cells in layers 3 and 5. Our proposed organization of cortex in gray squirrels includes both similarities and differences to the proposed of cortex in other rodents such as mice and rats. The presence of a number of well-differentiated cortical areas in squirrels may serve as a guide to the identification of homologous fields in other rodents, as well as a useful guide in further studies of cortical organization and function.
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Affiliation(s)
- Peiyan Wong
- Department of Psychology, Vanderbilt University, Nashville TN 37212
| | - Jon H. Kaas
- Department of Psychology, Vanderbilt University, Nashville TN 37212
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Patrignani C, Magnone MC, Tavano P, Ardizzone M, Muzio V, Gréco B, Zaratin PF. Knockout mice reveal a role for protein tyrosine phosphatase H1 in cognition. Behav Brain Funct 2008; 4:36. [PMID: 18700002 PMCID: PMC2531118 DOI: 10.1186/1744-9081-4-36] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2008] [Accepted: 08/12/2008] [Indexed: 11/10/2022] Open
Abstract
Background The present study has investigated the protein tyrosine phosphatase H1 (PTPH1) expression pattern in mouse brain and its impact on CNS functions. Methods We have previously described a PTPH1-KO mouse, generated by replacing the PTP catalytic and the PDZ domain with a LacZ neomycin cassette. PTPH1 expression pattern was evaluated by LacZ staining in the brain and PTPH1-KO and WT mice (n = 10 per gender per genotype) were also behaviorally tested for CNS functions. Results In CNS, PTPH1 is expressed during development and in adulthood and mainly localized in hippocampus, thalamus, cortex and cerebellum neurons. The behavioral tests performed on the PTPH1-KO mice showed an impact on working memory in male mice and an impaired learning performance at rotarod in females. Conclusion These results demonstrate for the first time a neuronal expression of PTPH1 and its functionality at the level of cognition.
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Miyashita T, Rockland KS. GABAergic projections from the hippocampus to the retrosplenial cortex in the rat. Eur J Neurosci 2007; 26:1193-204. [PMID: 17767498 DOI: 10.1111/j.1460-9568.2007.05745.x] [Citation(s) in RCA: 78] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The retrosplenial cortex (RS) in rats has been implicated in a wide range of behaviors, including spatial navigation and memory. Relevant to this, the RS is closely interconnected with the hippocampus by multiple direct and indirect routes. Here, by injecting the retrograde tracer cholera toxin subunit B conjugated with Alexa488 (CTB-Alexa488) in the granular retrosplenial cortex (GRS), we demonstrate a moderately dense non-pyramidal projection from CA1. Neurons are in several layers, but mainly (about 65%) at the border of the stratum radiatum (SR) and stratum lacunosum moleculare (SLM). In particular, by double-labeling with GAD67 or gamma-aminobutyric acid (GABA), we establish that these neurons are GABAergic. Further immunocytochemical screening for calcium-binding proteins, somatostatin (SS) or cholecystokinin (CCK) failed to identify additional neurochemical subgroups; but a small subset (about 14%) is positive for the m2 muscarinic acetylcholine receptor (M2R). Terminations target layer 1 of the GRS, as shown by biotinylated dextran amine (BDA) injections into CA1 and confirmed by a very superficial injection of CTB-Alexa488 in GRS. The superficial injection shows that there is a sparse GABAergic projection from the subiculum to layer 1 of the GRS, in addition to the dense excitatory connections to layer 3. The role of these dual inhibitory-excitatory pathways - within the subiculum, and in parallel from CA1 and the subiculum - remains to be determined, but may be related to synchronized oscillatory activity in the hippocampal complex and GRS, or to the generation of rhythmic activity within the GRS.
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Affiliation(s)
- Toshio Miyashita
- Laboratory for Cortical Organization and Systematics, RIKEN Brain Science Institute, 2-1 Hirosawa, Wako-shi, Saitama, 351-0198, Japan.
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Ichinohe N, Knight A, Ogawa M, Ohshima T, Mikoshiba K, Yoshihara Y, Terashima T, Rockland KS. Unusual patch-matrix organization in the retrosplenial cortex of the reeler mouse and Shaking rat Kawasaki. Cereb Cortex 2007; 18:1125-38. [PMID: 17728262 DOI: 10.1093/cercor/bhm148] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
The rat granular retrosplenial cortex (GRS) is a simplified cortex, with distinct stratification and, in the uppermost layers, distinct modularity. Thalamic and cortical inputs are segregated by layers and in layer 1 colocalize, respectively, with apical dendritic bundles originating from neurons in layers 2 or 5. To further investigate this organization, we turned to reelin-deficient reeler mouse and Shaking rat Kawasaki. We found that the disrupted lamination, evident in Nissl stains in these rodents, is in fact a patch-matrix mosaic of segregated afferents and dendrites. Patches consist of thalamocortical connections, visualized by vesicular glutamate transporter 2 (VGluT2) or AChE. The surrounding matrix consists of corticocortical terminations, visualized by VGluT1 or zinc. Dendrites concentrate in the matrix or patches, depending on whether they are OCAM positive (matrix) or negative (patches). In wild-type rodents and, presumably, mutants, OCAM(+) structures originate from layer 5 neurons. By double labeling for dendrites (filled by Lucifer yellow in fixed slice) and OCAM immunofluorescence, we ascertained 2 populations in reeler: dendritic branches either preferred (putative layer 5 neurons) or avoided (putative supragranular neurons) the OCAM(+) matrix. We conclude that input-target relationships are largely preserved in the mutant GRS and that dendrite-dendrite interactions involving OCAM influence the formation of the mosaic configuration.
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Affiliation(s)
- Noritaka Ichinohe
- Laboratory for Cortical Organization and Systematics, RIKEN, Brain Science Institute, Wako, Saitama 351-0198, Japan
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Ichinohe N, Potapov D, Rockland KS. Transient synaptic zinc-positive thalamocortical terminals in the developing barrel cortex. Eur J Neurosci 2006; 24:1001-10. [PMID: 16930427 DOI: 10.1111/j.1460-9568.2006.05000.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
In rat barrel cortex, layer 4 has a transiently high density of zinc-positive terminations from postnatal day (P)9 to P12 [P.W. Land & L. Shamalla-Hannah (2002)J. Comp. Neurol., 447, 43-56]. These terminations have been proposed to originate from cortico-cortical connections, but their exact origin is unknown. To determine their sources, we injected sodium selenite into the barrel cortex of two adult rats and 32 pups, from P5 to P28. As predicted, abundant zinc-positive cortically projecting neurons were visible around the injection sites and in distant cortical areas. From P9 to P13, however, neurons retrogradely labeled by zinc selenite occurred in the thalamus, in topographically appropriate regions of the ventroposterior medial (VPM) and posterior nuclei (Po). Because there are no previous reports of zinc-positive sensory thalamocortical connections, we sought corroboration of this unexpected finding by electron microscopy. This revealed a subset of boutons in layers 4 and 1, positive for both zinc and vesicular glutamate transporter 2, a protein used by thalamocortical terminations. Finally, in an additional nine rats, we carried out in situ hybridization for zinc transporter 3 mRNA. Moderate signal was detected in VPM and Po at P10, but this disappeared by P28. In contrast, a strong signal was apparent in the anterodorsal nucleus, which projects to limbic areas, and this persisted at P28. The timing of the transient zinc-positive terminations in the sensory thalamus roughly coincides with the onset of exploratory and whisking behavior in the middle of the second postnatal week; and this suggests zinc is important for activity-related refinement of circuitry.
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Affiliation(s)
- Noritaka Ichinohe
- Laboratory for Cortical Organization and Systematics, Brain Science Institute, RIKEN, 2-1 Hirosawa, Wako-shi, Saitama 351-0198, Japan.
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