1
|
Malungo IB, Mokale R, Bertelsen MF, Manger PR. Cholinergic, catecholaminergic, serotonergic, and orexinergic neuronal populations in the brain of the lesser hedgehog tenrec (Echinops telfairi). Anat Rec (Hoboken) 2023; 306:844-878. [PMID: 36179372 DOI: 10.1002/ar.25092] [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: 07/15/2022] [Revised: 09/26/2022] [Accepted: 09/26/2022] [Indexed: 11/07/2022]
Abstract
The current study provides an analysis of the cholinergic, catecholaminergic, serotonergic, and orexinergic neuronal populations, or nuclei, in the brain of the lesser hedgehog tenrec, as revealed with immunohistochemical techniques. For all four of these neuromodulatory systems, the nuclear organization was very similar to that observed in other Afrotherian species and is broadly similar to that observed in other mammals. The cholinergic system shows the most variation, with the lesser hedgehog tenrec exhibiting palely immunopositive cholinergic neurons in the ventral portion of the lateral septal nucleus, and the possible absence of cholinergic neurons in the parabigeminal nucleus and the medullary tegmental field. The nuclear complement of the catecholaminergic, serotonergic and orexinergic systems showed no specific variances in the lesser hedgehog tenrec when compared to other Afrotherians, or broadly with other mammals. A striking feature of the lesser hedgehog tenrec brain is a significant mesencephalic flexure that is observed in most members of the Tenrecoidea, as well as the closely related Chrysochlorinae (golden moles), but is not present in the greater otter shrew, a species of the Potomogalidae lineage currently incorporated into the Tenrecoidea. In addition, the cholinergic neurons of the ventral portion of the lateral septal nucleus are observed in the golden moles, but not in the greater otter shrew. This indicates that either complex parallel evolution of these features occurred in the Tenrecoidea and Chrysochlorinae lineages, or that the placement of the Potomogalidae within the Tenrecoidea needs to be re-examined.
Collapse
Affiliation(s)
- Illke B Malungo
- School of Anatomical Sciences, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, Republic of South Africa
| | - Reabetswe Mokale
- School of Anatomical Sciences, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, Republic of South Africa
| | - Mads F Bertelsen
- Centre for Zoo and Wild Animal Health, Copenhagen Zoo, Frederiksberg, Denmark
| | - Paul R Manger
- School of Anatomical Sciences, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, Republic of South Africa
| |
Collapse
|
2
|
Ai JQ, Luo R, Tu T, Yang C, Jiang J, Zhang B, Bi R, Tu E, Yao YG, Yan XX. Doublecortin-Expressing Neurons in Chinese Tree Shrew Forebrain Exhibit Mixed Rodent and Primate-Like Topographic Characteristics. Front Neuroanat 2021; 15:727883. [PMID: 34602987 PMCID: PMC8481370 DOI: 10.3389/fnana.2021.727883] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2021] [Accepted: 08/23/2021] [Indexed: 11/18/2022] Open
Abstract
Doublecortin (DCX) is transiently expressed in new-born neurons in the subventricular zone (SVZ) and subgranular zone (SGZ) related to adult neurogenesis in the olfactory bulb (OB) and hippocampal formation. DCX immunoreactive (DCX+) immature neurons also occur in the cerebral cortex primarily over layer II and the amygdala around the paralaminar nucleus (PLN) in various mammals, with interspecies differences pointing to phylogenic variation. The tree shrews (Tupaia belangeri) are phylogenetically closer to primates than to rodents. Little is known about DCX+ neurons in the brain of this species. In the present study, we characterized DCX immunoreactivity (IR) in the forebrain of Chinese tree shrews aged from 2 months- to 6 years-old (n = 18). DCX+ cells were present in the OB, SVZ, SGZ, the piriform cortex over layer II, and the amygdala around the PLN. The numerical densities of DCX+ neurons were reduced in all above neuroanatomical regions with age, particularly dramatic in the DG in the 5–6 years-old animals. Thus, DCX+ neurons are present in the two established neurogenic sites (SVZ and SGZ) in the Chinese tree shrew as seen in other mammals. DCX+ cortical neurons in this animal exhibit a topographic pattern comparable to that in mice and rats, while these immature neurons are also present in the amygdala, concentrating around the PLN as seen in primates and some nonprimate mammals.
Collapse
Affiliation(s)
- Jia-Qi Ai
- Department of Anatomy and Neurobiology, Central South University Xiangya School of Medicine, Changsha, China
| | - Rongcan Luo
- Key Laboratory of Animal Models and Human Disease Mechanisms of the Chinese Academy of Sciences & Yunan Province, and KIZ/CUHK Joint Laboratory of Bioresources and Molecular Research in Common Diseases, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, China
| | - Tian Tu
- Department of Neurology, Xiangya Hospital, Central South University, Changsha, China
| | - Chen Yang
- Department of Anatomy and Neurobiology, Central South University Xiangya School of Medicine, Changsha, China
| | - Juan Jiang
- Department of Anatomy and Neurobiology, Central South University Xiangya School of Medicine, Changsha, China
| | - Bo Zhang
- Department of Neurology, Brain Hospital of Hunan Province, Changsha, China
| | - Rui Bi
- Key Laboratory of Animal Models and Human Disease Mechanisms of the Chinese Academy of Sciences & Yunan Province, and KIZ/CUHK Joint Laboratory of Bioresources and Molecular Research in Common Diseases, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, China
| | - Ewen Tu
- Department of Neurology, Brain Hospital of Hunan Province, Changsha, China
| | - Yong-Gang Yao
- Key Laboratory of Animal Models and Human Disease Mechanisms of the Chinese Academy of Sciences & Yunan Province, and KIZ/CUHK Joint Laboratory of Bioresources and Molecular Research in Common Diseases, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, China.,Kunming College of Life Science, University of Chinese Academy of Sciences, Kunming, China.,CSA Center for Excellence in Brain Science and Intelligence Technology, Chinese Academy of Sciences, Shanghai, China
| | - Xiao-Xin Yan
- Department of Anatomy and Neurobiology, Central South University Xiangya School of Medicine, Changsha, China
| |
Collapse
|
3
|
Jacobs B, Rally H, Doyle C, O'Brien L, Tennison M, Marino L. Putative neural consequences of captivity for elephants and cetaceans. Rev Neurosci 2021; 33:439-465. [PMID: 34534428 DOI: 10.1515/revneuro-2021-0100] [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] [Received: 07/26/2021] [Accepted: 09/02/2021] [Indexed: 12/20/2022]
Abstract
The present review assesses the potential neural impact of impoverished, captive environments on large-brained mammals, with a focus on elephants and cetaceans. These species share several characteristics, including being large, wide-ranging, long-lived, cognitively sophisticated, highly social, and large-brained mammals. Although the impact of the captive environment on physical and behavioral health has been well-documented, relatively little attention has been paid to the brain itself. Here, we explore the potential neural consequences of living in captive environments, with a focus on three levels: (1) The effects of environmental impoverishment/enrichment on the brain, emphasizing the negative neural consequences of the captive/impoverished environment; (2) the neural consequences of stress on the brain, with an emphasis on corticolimbic structures; and (3) the neural underpinnings of stereotypies, often observed in captive animals, underscoring dysregulation of the basal ganglia and associated circuitry. To this end, we provide a substantive hypothesis about the negative impact of captivity on the brains of large mammals (e.g., cetaceans and elephants) and how these neural consequences are related to documented evidence for compromised physical and psychological well-being.
Collapse
Affiliation(s)
- Bob Jacobs
- Laboratory of Quantitative Neuromorphology, Neuroscience Program, Colorado College, Colorado Springs, CO, 80903, USA
| | - Heather Rally
- Foundation to Support Animal Protection, Norfolk, VA, 23510, USA
| | - Catherine Doyle
- Performing Animal Welfare Society, P.O. Box 849, Galt, CA, 95632, USA
| | - Lester O'Brien
- Palladium Elephant Consulting Inc., 2408 Pinewood Dr. SE, Calgary, AB, T2B1S4, Canada
| | - Mackenzie Tennison
- Department of Psychology, University of Washington, Seattle, WA, 98195, USA
| | - Lori Marino
- Whale Sanctuary Project, Kanab, UT, 84741, USA
| |
Collapse
|