1
|
Siegler PN, Shaughnessy EK, Horman B, Vierling TT, King DH, Patisaul HB, Huhman KL, Alexander GM, Dudek SM. Identification of hippocampal area CA2 in hamster and vole brain. J Comp Neurol 2024; 532:e25603. [PMID: 38497661 PMCID: PMC10950058 DOI: 10.1002/cne.25603] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2023] [Revised: 01/24/2024] [Accepted: 02/27/2024] [Indexed: 03/19/2024]
Abstract
Prairie voles (Microtus ochrogaster) and Syrian, or golden, hamsters (Mesocricetus auratus) are closely related to mice (Mus musculus) and are commonly used in studies of social behavior including social interaction, social memory, and aggression. Hippocampal area CA2 is known to play a key role in these behaviors in mice and responds to social stimuli in rats, but CA2 has yet to be characterized in hamsters or voles, which are also used in studies of social behaviors. Here, we used immunofluorescence to determine whether CA2 could be molecularly identified in tissue from voles and hamsters. We found that staining for many CA2 markers was similar in these three species, with labeling seen in neurons at the distal end of the mossy fibers . In contrast, although perineuronal nets (PNNs) surround CA2 cells in mice, PNN staining differed across species. In voles, both CA2 and CA3 were labeled, whereas in hamsters, labeling was seen primarily in CA3. These results demonstrate that CA2 can be molecularly distinguished from neighboring CA1 and CA3 areas in voles and hamsters with several antibodies commonly used in mice. However, PNN staining is not useful for identifying CA2 in voles or hamsters, suggestive of differing roles for either PNNs or for the hippocampal subregions in social behavior. These findings reveal commonalities across species in the molecular profile of CA2 and should facilitate future studies of CA2 in these species.
Collapse
Affiliation(s)
- Preston Nicole Siegler
- Neurobiology Laboratory, National Institute of Environmental Health Sciences, NIH, 111 T.W. Alexander Drive, Research Triangle Park, NC 27709 USA
- Neuroscience Center, University of North Carolina, Chapel Hill, NC
| | | | - Brian Horman
- Department of Biological Sciences, North Carolina State University, Raleigh, NC
| | - Tia T. Vierling
- Neurobiology Laboratory, National Institute of Environmental Health Sciences, NIH, 111 T.W. Alexander Drive, Research Triangle Park, NC 27709 USA
| | - Darron H. King
- Neurobiology Laboratory, National Institute of Environmental Health Sciences, NIH, 111 T.W. Alexander Drive, Research Triangle Park, NC 27709 USA
| | - Heather B. Patisaul
- Department of Biological Sciences, North Carolina State University, Raleigh, NC
| | - Kim L. Huhman
- Neuroscience Institute, Georgia State University, Atlanta, GA
| | - Georgia M. Alexander
- Neurobiology Laboratory, National Institute of Environmental Health Sciences, NIH, 111 T.W. Alexander Drive, Research Triangle Park, NC 27709 USA
| | - Serena M. Dudek
- Neurobiology Laboratory, National Institute of Environmental Health Sciences, NIH, 111 T.W. Alexander Drive, Research Triangle Park, NC 27709 USA
| |
Collapse
|
2
|
Siegler PN, Shaughnessy EK, Horman B, Vierling TT, King DH, Patisaul HB, Huhman KL, Alexander GM, Dudek SM. Identification of hippocampal area CA2 in hamster and vole brain. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.02.12.579957. [PMID: 38405991 PMCID: PMC10888814 DOI: 10.1101/2024.02.12.579957] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/27/2024]
Abstract
Prairie voles (Microtus ochrogaster) and Syrian, or golden, hamsters (Mesocricetus auratus) are closely related to mice (Mus musculus) and rats (Rattus norvegicus, for example) and are commonly used in studies of social behavior including social interaction, social memory, and aggression. The CA2 region of the hippocampus is known to play a key role in social memory and aggression in mice and responds to social stimuli in rats, likely owing to its high expression of oxytocin and vasopressin 1b receptors. However, CA2 has yet to be identified and characterized in hamsters or voles. In this study, we sought to determine whether CA2 could be identified molecularly in vole and hamster. To do this, we used immunofluorescence with primary antibodies raised against known molecular markers of CA2 in mice and rats to stain hippocampal sections from voles and hamsters in parallel with those from mice. Here, we report that, like in mouse and rat, staining for many CA2 proteins in vole and hamster hippocampus reveals a population of neurons that express regulator of G protein signaling 14 (RGS14), Purkinje cell protein 4 (PCP4) and striatal-enriched protein tyrosine phosphatase (STEP), which together delineate the borders with CA3 and CA1. These cells were located at the distal end of the mossy fiber projections, marked by the presence of Zinc Transporter 3 (ZnT-3) and calbindin in all three species. In addition to staining the mossy fibers, calbindin also labeled a layer of CA1 pyramidal cells in mouse and hamster but not in vole. However, Wolframin ER transmembrane glycoprotein (WFS1) immunofluorescence, which marks all CA1 neurons, was present in all three species and abutted the distal end of CA2, marked by RGS14 immunofluorescence. Staining for two stress hormone receptors-the glucocorticoid (GR) and mineralocorticoid (MR) receptors-was also similar in all three species, with GR staining found primarily in CA1 and MR staining enriched in CA2. Interestingly, although perineuronal nets (PNNs) are known to surround CA2 cells in mouse and rat, we found that staining for PNNs differed across species in that both CA2 and CA3 showed staining in voles and primarily CA3 in hamsters with only some neurons in proximal CA2 showing staining. These results demonstrate that, like in mouse, CA2 in voles and hamsters can be molecularly distinguished from neighboring CA1 and CA3 areas, but PNN staining is less useful for identifying CA2 in the latter two species. These findings reveal commonalities across species in molecular profile of CA2, which will facilitate future studies of CA2 in these species. Yet to be determined is how differences in PNNs might relate to differences in social behavior across species.
Collapse
Affiliation(s)
- Preston Nicole Siegler
- Neurobiology Laboratory, National Institute of Environmental Health Sciences, NIH, 111 T.W. Alexander Drive, Research Triangle Park, NC 27709 USA
- Neuroscience Center, University of North Carolina, Chapel Hill, NC
| | | | - Brian Horman
- Department of Biological Sciences, North Carolina State University, Raleigh, NC
| | - Tia T. Vierling
- Neurobiology Laboratory, National Institute of Environmental Health Sciences, NIH, 111 T.W. Alexander Drive, Research Triangle Park, NC 27709 USA
| | - Darron H. King
- Neurobiology Laboratory, National Institute of Environmental Health Sciences, NIH, 111 T.W. Alexander Drive, Research Triangle Park, NC 27709 USA
| | - Heather B. Patisaul
- Department of Biological Sciences, North Carolina State University, Raleigh, NC
| | - Kim L. Huhman
- Neuroscience Institute, Georgia State University, Atlanta, GA
| | - Georgia M. Alexander
- Neurobiology Laboratory, National Institute of Environmental Health Sciences, NIH, 111 T.W. Alexander Drive, Research Triangle Park, NC 27709 USA
| | - Serena M. Dudek
- Neurobiology Laboratory, National Institute of Environmental Health Sciences, NIH, 111 T.W. Alexander Drive, Research Triangle Park, NC 27709 USA
| |
Collapse
|
3
|
Takeuchi Y, Yamashiro K, Noguchi A, Liu J, Mitsui S, Ikegaya Y, Matsumoto N. Machine learning-based segmentation of the rodent hippocampal CA2 area from Nissl-stained sections. Front Neuroanat 2023; 17:1172512. [PMID: 37449243 PMCID: PMC10336234 DOI: 10.3389/fnana.2023.1172512] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2023] [Accepted: 06/05/2023] [Indexed: 07/18/2023] Open
Abstract
The hippocampus is a center of learning, memory, and spatial navigation. This region is divided into the CA1, CA2, and CA3 areas, which are anatomically different from each other. Among these divisions, the CA2 area is unique in terms of functional relevance to sociality. The CA2 area is often manually detected based on the size, shape, and density of neurons in the hippocampal pyramidal cell layer, but this manual segmentation relying on cytoarchitecture is impractical to apply to a large number of samples and dependent on experimenters' proficiency. Moreover, the CA2 area has been defined based on expression pattern of molecular marker proteins, but it generally takes days to complete immunostaining for such proteins. Thus, we asked whether the CA2 area can be systematically segmented based on cytoarchitecture alone. Since the expression pattern of regulator of G-protein signaling 14 (RGS14) signifies the CA2 area, we visualized the CA2 area in the mouse hippocampus by RGS14-immunostaining and Nissl-counterstaining and manually delineated the CA2 area. We then established "CAseg," a machine learning-based automated algorithm to segment the CA2 area with the F1-score of approximately 0.8 solely from Nissl-counterstained images that visualized cytoarchitecture. CAseg was extended to the segmentation of the prairie vole CA2 area, which raises the possibility that the use of this algorithm can be expanded to other species. Thus, CAseg will be beneficial for investigating unique properties of the hippocampal CA2 area.
Collapse
Affiliation(s)
- Yuki Takeuchi
- Graduate School of Pharmaceutical Sciences, The University of Tokyo, Tokyo, Japan
| | - Kotaro Yamashiro
- Graduate School of Pharmaceutical Sciences, The University of Tokyo, Tokyo, Japan
| | - Asako Noguchi
- Graduate School of Pharmaceutical Sciences, The University of Tokyo, Tokyo, Japan
| | - Jiayan Liu
- Graduate School of Pharmaceutical Sciences, The University of Tokyo, Tokyo, Japan
| | - Shinichi Mitsui
- Department of Rehabilitation Sciences, Graduate School of Health Sciences, Gunma University, Maebashi, Gunma, Japan
| | - Yuji Ikegaya
- Graduate School of Pharmaceutical Sciences, The University of Tokyo, Tokyo, Japan
- Institute for AI and Beyond, The University of Tokyo, Tokyo, Japan
- Center for Information and Neural Networks, National Institute of Information and Communications Technology, Osaka, Japan
| | - Nobuyoshi Matsumoto
- Graduate School of Pharmaceutical Sciences, The University of Tokyo, Tokyo, Japan
- Institute for AI and Beyond, The University of Tokyo, Tokyo, Japan
| |
Collapse
|
4
|
Dudek SM, Phoenix AN, Scappini E, Shepeleva DV, Herbeck YE, Trut LN, Farris S, Kukekova AV. Defining hippocampal area CA2 in the fox (Vulpes vulpes) brain. Hippocampus 2023; 33:700-711. [PMID: 37159095 PMCID: PMC10274530 DOI: 10.1002/hipo.23546] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2023] [Revised: 04/05/2023] [Accepted: 04/21/2023] [Indexed: 05/10/2023]
Abstract
Since 1959, the Russian Farm-Fox study has bred foxes to be either tame or, more recently, aggressive, and scientists have used them to gain insight into the brain structures associated with these behavioral features. In mice, hippocampal area CA2 has emerged as one of the essential regulators of social aggression, and so to eventually determine whether we could identify differences in CA2 between tame and aggressive foxes, we first sought to identify CA2 in foxes (Vulpes vulpes). As no clearly defined area of CA2 has been described in species such as cats, dogs, or pigs, it was not at all clear whether CA2 could be identified in foxes. In this study, we cut sections of temporal lobes from male and female red foxes, perpendicular to the long axis of the hippocampus, and stained them with markers of CA2 pyramidal cells commonly used in tissue from rats and mice. We observed that antibodies against Purkinje cell protein 4 best stained the pyramidal cells in the area spanning the end of the mossy fibers and the beginning of the pyramidal cells lacking mossy fibers, resembling the pattern seen in rats and mice. Our findings indicate that foxes do have a "molecularly defined" CA2, and further, they suggest that other carnivores like dogs and cats might as well. With this being the case, these foxes could be useful in future studies looking at CA2 as it relates to aggression.
Collapse
Affiliation(s)
- Serena M Dudek
- National Institute of Environmental Health Sciences, NIH, Research Triangle Park, Durham, North Carolina, USA
| | - Ashley N Phoenix
- National Institute of Environmental Health Sciences, NIH, Research Triangle Park, Durham, North Carolina, USA
| | - Erica Scappini
- National Institute of Environmental Health Sciences, NIH, Research Triangle Park, Durham, North Carolina, USA
| | - Darya V Shepeleva
- Siberian Branch of the Russian Academy of Sciences, Institute of Cytology and Genetics, Novosibirsk, Russian Federation
| | - Yury E Herbeck
- Siberian Branch of the Russian Academy of Sciences, Institute of Cytology and Genetics, Novosibirsk, Russian Federation
- Koret School of Veterinary Medicine, The Robert H. Smith Faculty of Agriculture, Food & Environment, The Hebrew University of Jerusalem, Rehovot, Israel
| | - Lyudmila N Trut
- Siberian Branch of the Russian Academy of Sciences, Institute of Cytology and Genetics, Novosibirsk, Russian Federation
| | - Shannon Farris
- Fralin Biomedical Research Institute, Virginia Tech, Roanoke, Virginia, USA
| | - Anna V Kukekova
- Department of Animal Science, The University of Illinois at Urbana-Champaign, Urbana, Illinois, USA
| |
Collapse
|
5
|
Dudek SM, Alexander GM, Farris S. Introduction to the special issue on: A new view of hippocampal area CA2. Hippocampus 2023; 33:127-132. [PMID: 36826426 DOI: 10.1002/hipo.23514] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/31/2023] [Indexed: 02/25/2023]
Affiliation(s)
- Serena M Dudek
- Neurobiology Laboratory, National Institute of Environmental Health Sciences, National Institute of Health, Research Triangle Park, North Carolina, USA
| | - Georgia M Alexander
- Neurobiology Laboratory, National Institute of Environmental Health Sciences, National Institute of Health, Research Triangle Park, North Carolina, USA
| | - Shannon Farris
- Center for Neurobiology Research, Fralin Biomedical Research Institute, Virginia Tech Carilion, Roanoke, Virginia, USA
| |
Collapse
|