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Pecheva D, Smith DM, Casey BJ, Woodward LJ, Dale AM, Filippi CG, Watts R. Sex and mental health are related to subcortical brain microstructure. Proc Natl Acad Sci U S A 2024; 121:e2403212121. [PMID: 39042688 PMCID: PMC11295051 DOI: 10.1073/pnas.2403212121] [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: 02/18/2024] [Accepted: 06/14/2024] [Indexed: 07/25/2024] Open
Abstract
Some mental health problems such as depression and anxiety are more common in females, while others such as autism and attention deficit/hyperactivity (AD/H) are more common in males. However, the neurobiological origins of these sex differences are poorly understood. Animal studies have shown substantial sex differences in neuronal and glial cell structure, while human brain imaging studies have shown only small differences, which largely reflect overall body and brain size. Advanced diffusion MRI techniques can be used to examine intracellular, extracellular, and free water signal contributions and provide unique insights into microscopic cellular structure. However, the extent to which sex differences exist in these metrics of subcortical gray matter structures implicated in psychiatric disorders is not known. Here, we show large sex-related differences in microstructure in subcortical regions, including the hippocampus, thalamus, and nucleus accumbens in a large sample of young adults. Unlike conventional T1-weighted structural imaging, large sex differences remained after adjustment for age and brain volume. Further, diffusion metrics in the thalamus and amygdala were associated with depression, anxiety, AD/H, and antisocial personality problems. Diffusion MRI may provide mechanistic insights into the origin of sex differences in behavior and mental health over the life course and help to bridge the gap between findings from experimental, epidemiological, and clinical mental health research.
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Affiliation(s)
- Diliana Pecheva
- Center for Multimodal Imaging and Genetics, University of California, San Diego, La Jolla, CA92093
| | - Diana M. Smith
- Center for Multimodal Imaging and Genetics, University of California, San Diego, La Jolla, CA92093
- Medical Scientist Training Program, University of California, San Diego, La Jolla, CA92093
| | - B. J. Casey
- Department of Neuroscience and Behavior, Barnard College, New York, NY10027
| | - Lianne J. Woodward
- Faculty of Health, University of Canterbury, Christchurch8140, New Zealand
| | - Anders M. Dale
- Center for Multimodal Imaging and Genetics, University of California, San Diego, La Jolla, CA92093
- Department of Radiology, University of California, San Diego, La Jolla, CA92093
- Department of Neurosciences, University of California, San Diego, La Jolla, CA92093
- Department of Psychiatry, University of California, San Diego, La Jolla, CA92093
| | - Christopher G. Filippi
- Department of Radiology, The Hospital for Sick Children and the SickKids Research Institute, Toronto, ON M5G 1E8, Canada
| | - Richard Watts
- Faculty of Health, University of Canterbury, Christchurch8140, New Zealand
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Menéndez-Delmestre R, Agosto-Rivera JL, González-Segarra AJ, Segarra AC. Cocaine sensitization in male rats requires activation of estrogen receptors. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.02.07.579327. [PMID: 38370714 PMCID: PMC10871307 DOI: 10.1101/2024.02.07.579327] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/20/2024]
Abstract
Gonadal steroids play a modulatory role in cocaine use disorders, and are responsible for many sex differences observed in the behavioral response to cocaine. In females, it is well established that estradiol enhances the behavioral response to cocaine. In males, we have recently shown that testosterone enhances sensitization to cocaine but its mechanism of action remains to be elucidated. The current study investigated the contribution of DHT, a non-aromatizable androgen, and of estradiol, in regulating cocaine-induced sensitization in male rats. Gonadectomized (GDX) male rats treated with estradiol sensitized to repeated cocaine administration, while GDX rats treated with DHT did not, implicating estradiol in cocaine sensitization. Furthermore, intact male rats treated with the antiestrogen ICI 182,780 did not show sensitization to repeated cocaine. This study demonstrates the pivotal role of estradiol in cocaine-induced neuroplasticity and neuroadaptations in the rodent brain.
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Affiliation(s)
- Raissa Menéndez-Delmestre
- Physiology Department, School of Medicine, University of Puerto Rico, Medical Sciences Campus, PO Box 365067, San Juan, Puerto Rico 00936-5067
| | - José L. Agosto-Rivera
- Department of Biology, University of Puerto Rico, Río Piedras Campus, PO Box 23360, San Juan, Puerto Rico 00931-3360
| | - Amanda J González-Segarra
- Department of Neuroscience and Behavior, Barnard College, Columbia University, New York, New York 10027
| | - Annabell C. Segarra
- Physiology Department, School of Medicine, University of Puerto Rico, Medical Sciences Campus, PO Box 365067, San Juan, Puerto Rico 00936-5067
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3
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Simmons SC, Grecco GG, Atwood BK, Nugent FS. Effects of prenatal opioid exposure on synaptic adaptations and behaviors across development. Neuropharmacology 2023; 222:109312. [PMID: 36334764 PMCID: PMC10314127 DOI: 10.1016/j.neuropharm.2022.109312] [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: 09/09/2022] [Revised: 10/26/2022] [Accepted: 10/27/2022] [Indexed: 11/06/2022]
Abstract
In this review, we focus on prenatal opioid exposure (POE) given the significant concern for the mental health outcomes of children with parents affected by opioid use disorder (OUD) in the view of the current opioid crisis. We highlight some of the less explored interactions between developmental age and sex on synaptic plasticity and associated behavioral outcomes in preclinical POE research. We begin with an overview of the rich literature on hippocampal related behaviors and plasticity across POE exposure paradigms. We then discuss recent work on reward circuit dysregulation following POE. Additional risk factors such as early life stress (ELS) could further influence synaptic and behavioral outcomes of POE. Therefore, we include an overview on the use of preclinical ELS models where ELS exposure during key critical developmental periods confers considerable vulnerability to addiction and stress psychopathology. Here, we hope to highlight the similarity between POE and ELS on development and maintenance of opioid-induced plasticity and altered opioid-related behaviors where similar enduring plasticity in reward circuits may occur. We conclude the review with some of the limitations that should be considered in future investigations. This article is part of the Special Issue on 'Opioid-induced addiction'.
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Affiliation(s)
- Sarah C Simmons
- Department of Pharmacology and Molecular Therapeutics, School of Medicine, Uniformed Services University of the Health Sciences, Bethesda, MD, USA
| | - Greg G Grecco
- Department of Pharmacology & Toxicology, Indiana University School of Medicine, Indianapolis, IN, USA; Medical Scientist Training Program, Indiana University School of Medicine, Indianapolis, IN, 46202, USA
| | - Brady K Atwood
- Department of Pharmacology & Toxicology, Indiana University School of Medicine, Indianapolis, IN, USA; Stark Neurosciences Research Institute, Indiana University School of Medicine, Indianapolis, IN, 46202, USA
| | - Fereshteh S Nugent
- Department of Pharmacology and Molecular Therapeutics, School of Medicine, Uniformed Services University of the Health Sciences, Bethesda, MD, USA.
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Rasia-Filho AA, Calcagnotto ME, von Bohlen Und Halbach O. Introduction: What Are Dendritic Spines? ADVANCES IN NEUROBIOLOGY 2023; 34:1-68. [PMID: 37962793 DOI: 10.1007/978-3-031-36159-3_1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2023]
Abstract
Dendritic spines are cellular specializations that greatly increase the connectivity of neurons and modulate the "weight" of most postsynaptic excitatory potentials. Spines are found in very diverse animal species providing neural networks with a high integrative and computational possibility and plasticity, enabling the perception of sensorial stimuli and the elaboration of a myriad of behavioral displays, including emotional processing, memory, and learning. Humans have trillions of spines in the cerebral cortex, and these spines in a continuum of shapes and sizes can integrate the features that differ our brain from other species. In this chapter, we describe (1) the discovery of these small neuronal protrusions and the search for the biological meaning of dendritic spines; (2) the heterogeneity of shapes and sizes of spines, whose structure and composition are associated with the fine-tuning of synaptic processing in each nervous area, as well as the findings that support the role of dendritic spines in increasing the wiring of neural circuits and their functions; and (3) within the intraspine microenvironment, the integration and activation of signaling biochemical pathways, the compartmentalization of molecules or their spreading outside the spine, and the biophysical properties that can affect parent dendrites. We also provide (4) examples of plasticity involving dendritic spines and neural circuits relevant to species survival and comment on (5) current research advancements and challenges in this exciting research field.
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Affiliation(s)
- Alberto A Rasia-Filho
- Department of Basic Sciences/Physiology and Graduate Program in Biosciences, Universidade Federal de Ciências da Saúde de Porto Alegre, Porto Alegre, RS, Brazil
- Graduate Program in Neuroscience, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil
| | - Maria Elisa Calcagnotto
- Graduate Program in Neuroscience, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil
- Department of Biochemistry, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil
- Graduate Program in Biochemistry, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil
- Graduate Program in Psychiatry and Behavioral Science, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil
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Mi S, Chen H, Lin P, Kang P, Qiao D, Zhang B, Wang Z, Zhang J, Hu X, Wang C, Cui H, Li S. CaMKII is a modulator in neurodegenerative diseases and mediates the effect of androgen on synaptic protein PSD95. Front Genet 2022; 13:959360. [PMID: 35991539 PMCID: PMC9386121 DOI: 10.3389/fgene.2022.959360] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2022] [Accepted: 06/29/2022] [Indexed: 11/29/2022] Open
Abstract
Androgens rapidly regulate synaptic plasticity in hippocampal neurones, but the underlying mechanisms remain unclear. In this study, we carried out a comprehensive bioinformatics analysis of functional similarities between androgen receptor (AR) and the synaptic protein postsynaptic density 95 (PSD95) to evaluate the effect. Using different measurements and thresholds, we obtained consistent results illustrating that the two proteins were significantly involved in similar pathways. We further identified CaMKII plays a critical role in mediating the rapid effect of androgen and promoting the expression of PSD95. We used mouse hippocampal neurone HT22 cells as a cell model to investigate the effect of testosterone (T) on intracellular Ca2+ levels and the mechanism. Calcium imaging experiments showed that intracellular Ca2+ increased to a peak due to calcium influx in the extracellular fluid through L-type and N-type voltage-gated calcium channels when HT22 cells were treated with 100 nM T for 20 min. Subsequently, we investigated whether the Ca2+/CaMKII signaling pathway mediates the rapid effect of T, promoting the expression of the synaptic protein PSD95. Immunofluorescence cytochemical staining and western blotting results showed that T promoted CaMKII phosphorylation by rapidly increasing extracellular Ca2+ influx, thus increasing PSD95 expression. This study demonstrated that CaMKII acts as a mediator assisting androgen which regulates the synaptic protein PSD95Also, it provides evidence for the neuroprotective mechanisms of androgens in synaptic plasticity and reveals the gated and pharmacological mechanisms of the voltage-gated Ca2+ channel family for androgen replacement therapy.
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Affiliation(s)
- Shixiong Mi
- Department of Anatomy, Hebei Medical University, Shijiazhuang, China
- Neuroscience Research Center, Hebei Medical University, Shijiazhuang, China
- Hebei Key Laboratory of Neurodegenerative Disease Mechanism, Shijiazhuang, China
| | - Huan Chen
- Department of Anatomy, Hebei Medical University, Shijiazhuang, China
- Neuroscience Research Center, Hebei Medical University, Shijiazhuang, China
| | - Peijing Lin
- School of Food Science and Engineering, South China University of Technology, Guangzhou, China
| | - Peiyuan Kang
- Clinical Medicine, Hebei Medical University, Shijiazhuang, China
| | - Dan Qiao
- Department of Anatomy, Hebei Medical University, Shijiazhuang, China
- Neuroscience Research Center, Hebei Medical University, Shijiazhuang, China
| | - Bohan Zhang
- Department of Anatomy, Hebei Medical University, Shijiazhuang, China
- Neuroscience Research Center, Hebei Medical University, Shijiazhuang, China
| | - Zhao Wang
- Department of Anatomy, Hebei Medical University, Shijiazhuang, China
- Neuroscience Research Center, Hebei Medical University, Shijiazhuang, China
| | - Jingbao Zhang
- Basic Medicine, Hebei Medical University, Shijiazhuang, China
| | - Xiangting Hu
- Basic Medicine, Hebei Medical University, Shijiazhuang, China
| | - Chang Wang
- Department of Anatomy, Hebei Medical University, Shijiazhuang, China
- Neuroscience Research Center, Hebei Medical University, Shijiazhuang, China
- Hebei Key Laboratory of Neurodegenerative Disease Mechanism, Shijiazhuang, China
| | - Huixian Cui
- Department of Anatomy, Hebei Medical University, Shijiazhuang, China
- Neuroscience Research Center, Hebei Medical University, Shijiazhuang, China
- Hebei Key Laboratory of Neurodegenerative Disease Mechanism, Shijiazhuang, China
- *Correspondence: Sha Li, ; Huixian Cui,
| | - Sha Li
- Department of Anatomy, Hebei Medical University, Shijiazhuang, China
- Neuroscience Research Center, Hebei Medical University, Shijiazhuang, China
- Hebei Key Laboratory of Neurodegenerative Disease Mechanism, Shijiazhuang, China
- The Key Laboratory of Neural and Vascular Biology, Ministry of Education, Hebei Medical University, Shijiazhuang, China
- *Correspondence: Sha Li, ; Huixian Cui,
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Immature excitatory neurons in the amygdala come of age during puberty. Dev Cogn Neurosci 2022; 56:101133. [PMID: 35841648 PMCID: PMC9289873 DOI: 10.1016/j.dcn.2022.101133] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2022] [Revised: 06/23/2022] [Accepted: 07/08/2022] [Indexed: 11/21/2022] Open
Abstract
The human amygdala is critical for emotional learning, valence coding, and complex social interactions, all of which mature throughout childhood, puberty, and adolescence. Across these ages, the amygdala paralaminar nucleus (PL) undergoes significant structural changes including increased numbers of mature neurons. The PL contains a large population of immature excitatory neurons at birth, some of which may continue to be born from local progenitors. These progenitors disappear rapidly in infancy, but the immature neurons persist throughout childhood and adolescent ages, indicating that they develop on a protracted timeline. Many of these late-maturing neurons settle locally within the PL, though a small subset appear to migrate into neighboring amygdala subnuclei. Despite its prominent growth during postnatal life and possible contributions to multiple amygdala circuits, the function of the PL remains unknown. PL maturation occurs predominately during late childhood and into puberty when sex hormone levels change. Sex hormones can promote developmental processes such as neuron migration, dendritic outgrowth, and synaptic plasticity, which appear to be ongoing in late-maturing PL neurons. Collectively, we describe how the growth of late-maturing neurons occurs in the right time and place to be relevant for amygdala functions and neuropsychiatric conditions.
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7
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Methods and Challenges in Investigating Sex-Specific Consequences of Social Stressors in Adolescence in Rats: Is It the Stress or the Social or the Stage of Development? Curr Top Behav Neurosci 2021; 54:23-58. [PMID: 34455576 DOI: 10.1007/7854_2021_245] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
Adolescence is a time of social learning and social restructuring that is accompanied by changes in both the hypothalamic-pituitary-gonadal axis and the hypothalamic-pituitary-adrenal (HPA) axis. The activation of these axes by puberty and stressors, respectively, shapes adolescent development. Models of social stress in rats are used to understand the consequences of perturbations of the social environment for ongoing brain development. This paper reviews the challenges in investigating the sex-specific consequences of social stressors, sex differences in the models of social stress used in rats and the sex-specific effects on behaviour and provides an overview of sex differences in HPA responding to stressors, the variability in pubertal development and in strains of rats that require consideration in conducting such research, and directions for future research.
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Gobbo DR, Pereira LDS, Ferreira JGP, de Castro Horta-Junior JA, Bittencourt JC, Sá SI. Effects of ovariectomy on the inputs from the medial nucleus of the amygdala to the ventromedial nucleus of the hypothalamus in young adult rats. Neurosci Lett 2021; 746:135657. [PMID: 33482312 DOI: 10.1016/j.neulet.2021.135657] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2020] [Accepted: 01/12/2021] [Indexed: 10/22/2022]
Abstract
During puberty, sexual hormones induce crucial changes in neural circuit organization, leading to significant sexual dimorphism in adult behaviours. The ventrolateral division of the ventromedial nucleus of the hypothalamus (VMHvl) is the major neural site controlling the receptive component of female sexual behaviour, which is dependent on ovarian hormones. The inputs to the VMHvl, originating from the medial nucleus of the amygdala (MeA), transmit essential information to trigger such behaviour. In this study, we investigated the projection pattern of the MeA to the VMHvl in ovariectomized rats at early puberty. Six-week-old Sprague-Dawley rats were ovariectomized (OVX) and, upon reaching 90 days of age, were subjected to iontophoretic injections of the neuronal anterograde tracer Phaseolus vulgaris leucoagglutinin into the MeA. Projections from the MeA to the VMHvl and to other structures included in the neural circuit responsible for female sexual behaviour were analysed in the Control and OVX groups. The results of the semi-quantitative analysis showed that peripubertal ovariectomy reduced the density of intra-amygdalar fibres. The stereological estimates, however, failed to find changes in the organization of the terminal fields of nerve fibres from the MeA to the VMHvl in the adult. The present data show that ovariectomized rats during the peripubertal phase did not undergo significant changes in MeA fibres reaching the VMHvl; however, they suggest a possible effect of ovariectomy on MeA connectivity under amygdalar subnuclei.
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Affiliation(s)
- Denise Ribeiro Gobbo
- Universidade de Sao Paulo, Instituto de Ciencias Biomedicas, Laboratorio de Neuroanatomia Quimica, Departamento de Anatomia, Sao Paulo, SP, Brazil
| | - Lais da Silva Pereira
- Universidade de Sao Paulo, Instituto de Ciencias Biomedicas, Laboratorio de Neuroanatomia Quimica, Departamento de Anatomia, Sao Paulo, SP, Brazil
| | - Jozélia Gomes Pacheco Ferreira
- Universidade de Sao Paulo, Instituto de Ciencias Biomedicas, Laboratorio de Neuroanatomia Quimica, Departamento de Anatomia, Sao Paulo, SP, Brazil
| | | | - Jackson Cioni Bittencourt
- Universidade de Sao Paulo, Instituto de Ciencias Biomedicas, Laboratorio de Neuroanatomia Quimica, Departamento de Anatomia, Sao Paulo, SP, Brazil; Universidade de Sao Paulo, Instituto de Psicologia, Nucleo de Neurociências e Comportamento, São Paulo, SP, Brazil.
| | - Susana Isabel Sá
- Department of Biomedicine, Unit of Anatomy, Faculty of Medicine, University of Porto, Porto, Portugal; CINTESIS, Center for Health Technology and Services Research, Faculty of Medicine, University of Porto, Porto, Portugal.
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Huijgens PT, Snoeren EMS, Meisel RL, Mermelstein PG. Effects of gonadectomy and dihydrotestosterone on neuronal plasticity in motivation and reward related brain regions in the male rat. J Neuroendocrinol 2021; 33:e12918. [PMID: 33340384 DOI: 10.1111/jne.12918] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/02/2020] [Revised: 09/25/2020] [Accepted: 11/02/2020] [Indexed: 12/22/2022]
Abstract
Gonadal hormones affect neuronal morphology to ultimately regulate behaviour. In female rats, oestradiol mediates spine plasticity in hypothalamic and limbic brain structures, contributing to long-lasting effects on motivated behaviour. Parallel effects of androgens in male rats have not been extensively studied. Here, we investigated the effect of both castration and androgen replacement on spine plasticity in the nucleus accumbens shell and core (NAcSh and NAcC), caudate putamen (CPu), medial amygdala (MeA) and medial preoptic nucleus (MPN). Intact and castrated (gonadectomy [GDX]) male rats were treated with dihydrotestosterone (DHT, 1.5 mg) or vehicle (oil) in three experimental groups: intact-oil, GDX-oil and GDX-DHT. Spine density and morphology, measured 24 hours after injection, were determined through three-dimensional reconstruction of confocal z-stacks of DiI-labelled dendritic segments. We found that GDX decreased spine density in the MPN, which was rescued by DHT treatment. DHT also increased spine density in the MeA in GDX animals compared to intact oil-treated animals. By contrast, DHT decreased spine density in the NAcSh compared to GDX males. No effect on spine density was observed in the NAcC or CPu. Spine length and spine head diameter were unaffected by GDX and DHT in the investigated brain regions. In addition, immunohistochemistry revealed that DHT treatment of GDX animals rapidly increased the number of cell bodies in the NAcSh positive for phosphorylated cAMP response-element binding protein, a downstream messenger of the androgen receptor. These findings indicate that androgen signalling plays a role in the regulation of spine plasticity within neurocircuits involved in motivated behaviours.
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Affiliation(s)
- Patty T Huijgens
- Department of Neuroscience, University of Minnesota, Minneapolis, MN, USA
- Department of Psychology, UiT The Arctic University of Norway, Tromsø, Norway
| | - Eelke M S Snoeren
- Department of Psychology, UiT The Arctic University of Norway, Tromsø, Norway
| | - Robert L Meisel
- Department of Neuroscience, University of Minnesota, Minneapolis, MN, USA
| | - Paul G Mermelstein
- Department of Neuroscience, University of Minnesota, Minneapolis, MN, USA
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Premachandran H, Zhao M, Arruda-Carvalho M. Sex Differences in the Development of the Rodent Corticolimbic System. Front Neurosci 2020; 14:583477. [PMID: 33100964 PMCID: PMC7554619 DOI: 10.3389/fnins.2020.583477] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2020] [Accepted: 09/01/2020] [Indexed: 12/18/2022] Open
Abstract
In recent years, a growing body of research has shown sex differences in the prevalence and symptomatology of psychopathologies, such as depression, anxiety, and fear-related disorders, all of which show high incidence rates in early life. This has highlighted the importance of including female subjects in animal studies, as well as delineating sex differences in neural processing across development. Of particular interest is the corticolimbic system, comprising the hippocampus, amygdala, and medial prefrontal cortex. In rodents, these corticolimbic regions undergo dynamic changes in early life, and disruption to their normative development is believed to underlie the age and sex-dependent effects of stress on affective processing. In this review, we consolidate research on sex differences in the hippocampus, amygdala, and medial prefrontal cortex across early development. First, we briefly introduce current principles on sexual differentiation of the rodent brain. We then showcase corticolimbic regional sex differences in volume, morphology, synaptic organization, cell proliferation, microglia, and GABAergic signaling, and explain how these differences are influenced by perinatal and pubertal gonadal hormones. In compiling this research, we outline evidence of what and when sex differences emerge in the developing corticolimbic system, and illustrate how temporal dynamics of its maturational trajectory may differ in male and female rodents. This will help provide insight into potential neural mechanisms underlying sex-specific critical windows for stress susceptibility and behavioral emergence.
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Affiliation(s)
| | - Mudi Zhao
- Department of Psychology, University of Toronto Scarborough, Toronto, ON, Canada
| | - Maithe Arruda-Carvalho
- Department of Psychology, University of Toronto Scarborough, Toronto, ON, Canada.,Department of Cell and Systems Biology, University of Toronto Scarborough, Toronto, ON, Canada
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11
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Laube C, van den Bos W, Fandakova Y. The relationship between pubertal hormones and brain plasticity: Implications for cognitive training in adolescence. Dev Cogn Neurosci 2020; 42:100753. [PMID: 32072931 PMCID: PMC7005587 DOI: 10.1016/j.dcn.2020.100753] [Citation(s) in RCA: 67] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2019] [Revised: 12/20/2019] [Accepted: 01/07/2020] [Indexed: 12/12/2022] Open
Abstract
Adolescence may mark a sensitive period for the development of higher-order cognition through enhanced plasticity of cortical circuits. At the same time, animal research indicates that pubertal hormones may represent one key mechanism for closing sensitive periods in the associative neocortex, thereby resulting in decreased plasticity of cortical circuits in adolescence. In the present review, we set out to solve some of the existing ambiguity and examine how hormonal changes associated with pubertal onset may modulate plasticity in higher-order cognition during adolescence. We build on existing age-comparative cognitive training studies to explore how the potential for change in neural resources and behavioral repertoire differs across age groups. We review animal and human brain imaging studies, which demonstrate a link between brain development, neurochemical mechanisms of plasticity, and pubertal hormones. Overall, the existent literature indicates that pubertal hormones play a pivotal role in regulating the mechanisms of experience-dependent plasticity during adolescence. However, the extent to which hormonal changes associated with pubertal onset increase or decrease brain plasticity may depend on the specific cognitive domain, the sex, and associated brain networks. We discuss implications for future research and suggest that systematical longitudinal assessments of pubertal change together with cognitive training interventions may be a fruitful way toward a better understanding of adolescent plasticity. As the age of pubertal onset is decreasing across developed societies, this may also have important educational and clinical implications, especially with respect to the effects that earlier puberty has on learning.
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Affiliation(s)
- Corinna Laube
- Center for Lifespan Psychology, Max Planck Institute for Human Development, Berlin, Germany
| | | | - Yana Fandakova
- Center for Lifespan Psychology, Max Planck Institute for Human Development, Berlin, Germany.
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Guo Y, Chen Y, Yang M, Xu X, Lin Z, Ma J, Chen H, Hu Y, Ma Y, Wang X, Tian X. A Rare KIF1A Missense Mutation Enhances Synaptic Function and Increases Seizure Activity. Front Genet 2020; 11:61. [PMID: 32174959 PMCID: PMC7056823 DOI: 10.3389/fgene.2020.00061] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2019] [Accepted: 01/17/2020] [Indexed: 12/18/2022] Open
Abstract
Although genetic factors are considered a main etiology of epilepsy, the causes of genetic epilepsy in the majority of epilepsy patients remain unknown. Kinesin family member 1A (KIF1A), a neuron-specific motor protein that moves along with microtubules, is responsible for the transport of membranous organelles and synaptic vesicles. Variants of KIF1A have recently been associated with hereditary spastic paraplegia (HSP), hereditary sensory and autonomic neuropathy type 2 (HSANII), and intellectual disability. However, mutations in KIF1A have not been detected in patients with epilepsy. In our study, we conducted customized sequencing of epilepsy-related genes of a family with six patients with generalized epilepsy over three generations and identified a rare heterozygous mutation (c.1190C > A, p. Ala397Asp) in KIF1A. Whole-cell recordings from primary cultured neurons revealed that the mutant KIF1A increases the excitatory synaptic transmission but not the intrinsic excitability of neurons, and phenotype testing in zebrafish showed that this rare mutation results in epileptic seizure-like activity. These results provide new evidence demonstrating that KIF1A dysfunction is involved in epileptogenesis.
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Affiliation(s)
- Yi Guo
- Department of Neurology, The First Affiliated Hospital of Chongqing Medical University, Chongqing Key Laboratory of Neurology, Chongqing, China
| | - Yuanyuan Chen
- Department of Neurology, The First Affiliated Hospital of Chongqing Medical University, Chongqing Key Laboratory of Neurology, Chongqing, China
| | - Min Yang
- Department of Neurology, The First Affiliated Hospital of Chongqing Medical University, Chongqing Key Laboratory of Neurology, Chongqing, China
| | - Xin Xu
- Department of Neurology, The First Affiliated Hospital of Chongqing Medical University, Chongqing Key Laboratory of Neurology, Chongqing, China
| | - Zijun Lin
- Department of Neurology, The First Affiliated Hospital of Chongqing Medical University, Chongqing Key Laboratory of Neurology, Chongqing, China
| | - Junhong Ma
- Center of Epilepsy, Beijing Institute for Brain Disorders, Beijing, China
| | - Hongnian Chen
- Department of Neurology, The First Affiliated Hospital of Chongqing Medical University, Chongqing Key Laboratory of Neurology, Chongqing, China
| | - Yida Hu
- Department of Neurology, The First Affiliated Hospital of Chongqing Medical University, Chongqing Key Laboratory of Neurology, Chongqing, China
| | - Yuanlin Ma
- Department of Neurology, The First Affiliated Hospital of Chongqing Medical University, Chongqing Key Laboratory of Neurology, Chongqing, China
| | - Xuefeng Wang
- Department of Neurology, The First Affiliated Hospital of Chongqing Medical University, Chongqing Key Laboratory of Neurology, Chongqing, China
| | - Xin Tian
- Department of Neurology, The First Affiliated Hospital of Chongqing Medical University, Chongqing Key Laboratory of Neurology, Chongqing, China
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13
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Dalpian F, Rasia-Filho AA, Calcagnotto ME. Sexual dimorphism, estrous cycle and laterality determine the intrinsic and synaptic properties of medial amygdala neurons in rat. J Cell Sci 2019; 132:jcs.227793. [PMID: 30967401 DOI: 10.1242/jcs.227793] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2018] [Accepted: 03/29/2019] [Indexed: 01/06/2023] Open
Abstract
The posterodorsal medial amygdala (MePD) is a sex steroid-sensitive area that modulates different social behavior by relaying chemosensorial information to hypothalamic nuclei. However, little is known about MePD cell type diversity and functional connectivity. Here, we have characterized neurons and synaptic inputs in the right and left MePD of adult male and cycling female (in diestrus, proestrus or estrus) rats. Based on their electrophysiological properties and morphology, we found two coexisting subpopulations of spiny neurons that are sexually dimorphic. They were classified as Class I (predominantly bitufted-shaped neurons showing irregular spikes with frequency adaptation) or Class II (predominantly stellate-shaped neurons showing full spike frequency adaptation). Furthermore, excitatory and inhibitory inputs onto MePD cells were modulated by sex, estrous cycle and hemispheric lateralization. In the left MePD, there was an overall increase in the excitatory input to neurons of males compared to cycling females. However, in proestrus, the MePD neurons received mainly inhibitory inputs. Our findings indicate the existence of hemispheric lateralization, estrous cycle and sexual dimorphism influences at cellular and synaptic levels in the adult rat MePD.
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Affiliation(s)
- Francine Dalpian
- Graduate Program in Neuroscience, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS 90170-050, Brazil
| | - Alberto A Rasia-Filho
- Graduate Program in Neuroscience, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS 90170-050, Brazil.,Department of Basic Sciences/Physiology, Federal University of Health Sciences, Porto Alegre, RS 90170-050, Brazil
| | - Maria Elisa Calcagnotto
- Graduate Program in Neuroscience, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS 90170-050, Brazil .,Neurophysiology and Neurochemistry of Neuronal Excitability and Synaptic Plasticity Laboratory, Department of Biochemistry, ICBS, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS 90035-003, Brazil
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14
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Vásquez CE, Reberger R, Dall'Oglio A, Calcagnotto ME, Rasia-Filho AA. Neuronal types of the human cortical amygdaloid nucleus. J Comp Neurol 2018; 526:2776-2801. [PMID: 30156296 DOI: 10.1002/cne.24527] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2018] [Revised: 08/14/2018] [Accepted: 08/15/2018] [Indexed: 12/29/2022]
Abstract
The human cortical amygdaloid nucleus (CoA) receives exteroceptive sensory stimuli, modulates the functions coded by the intrinsic amygdaloid circuit, and constitutes the beginning of the limbic lobe continuum with direct and indirect connections toward subcortical, allocortical, and higher order neocortical areas. To provide basic data on the human CoA, we characterized and classified the neurons using the thionin and the "single-section" Golgi method adapted for postmortem brain tissue and light microscopy. We found 10 different types of neurons named according to the morphological features of the cell body, dendritic branches, and spine distribution. Most cells are multipolar spiny neurons with two or more primary dendrites, including pyramidal-like ones. Three-dimensional reconstructions evidenced the types and diversity of the dendritic spines in each neuron. The unlike density of spines along dendritic branches, from proximal to distal ones, indicate that the synaptic processing and plasticity can be different in each CoA neuron. Our study provides novel data on the neuronal composition of the human CoA indicating that the variety of cells in this region can have phylogenetic, ontogenetic, morphological, and likely functional implications for the integrated human brain function. This can reflect both a more complex subcortical synaptic processing of sensory and emotional information and an adaptation for species-specific social behavior display.
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Affiliation(s)
- Carlos Escobar Vásquez
- Neuroscience Graduate Program, Federal University of Rio Grande do Sul, Porto Alegre, Rio Grande do Sul, Brazil
| | - Roman Reberger
- Friedrich Alexander Universität Erlangen-Nürnberg, Medical Engineering Program, Erlangen, Germany
| | - Aline Dall'Oglio
- Department of Basic Sciences/Physiology, Federal University of Health Sciences of Porto Alegre, Porto Alegre, Rio Grande do Sul, Brazil
| | - Maria Elisa Calcagnotto
- Neuroscience Graduate Program, Federal University of Rio Grande do Sul, Porto Alegre, Rio Grande do Sul, Brazil.,Biochemistry Graduate Program, Neurophysiology and Neurochemistry of Neuronal Excitability and Synaptic Plasticity Laboratory, Department of Biochemistry, Universidade Federal do Rio Grande do Sul, Porto Alegre, Rio Grande do Sul, Brazil
| | - Alberto A Rasia-Filho
- Neuroscience Graduate Program, Federal University of Rio Grande do Sul, Porto Alegre, Rio Grande do Sul, Brazil.,Department of Basic Sciences/Physiology, Federal University of Health Sciences of Porto Alegre, Porto Alegre, Rio Grande do Sul, Brazil
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15
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Zancan M, Cunha RSR, Schroeder F, Xavier LL, Rasia‐Filho AA. Remodeling of the number and structure of dendritic spines in the medial amygdala: From prepubertal sexual dimorphism to puberty and effect of sexual experience in male rats. Eur J Neurosci 2018; 48:1851-1865. [DOI: 10.1111/ejn.14052] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2017] [Revised: 04/18/2018] [Accepted: 06/13/2018] [Indexed: 12/21/2022]
Affiliation(s)
- Mariana Zancan
- Department of Basic Sciences/PhysiologyFederal University of Health Sciences Porto Alegre Brazil
- Graduation Program in NeuroscienceFederal University of Rio Grande do Sul Porto Alegre Brazil
| | - Rick Shandler R. Cunha
- Department of Basic Sciences/PhysiologyFederal University of Health Sciences Porto Alegre Brazil
| | - Francielle Schroeder
- Laboratory of Tissue BiologyFaculty of BiosciencesPontifical Catholic University of Rio Grande do Sul (PUCRS) Porto Alegre Brazil
| | - Léder L. Xavier
- Laboratory of Tissue BiologyFaculty of BiosciencesPontifical Catholic University of Rio Grande do Sul (PUCRS) Porto Alegre Brazil
| | - Alberto A. Rasia‐Filho
- Department of Basic Sciences/PhysiologyFederal University of Health Sciences Porto Alegre Brazil
- Graduation Program in NeuroscienceFederal University of Rio Grande do Sul Porto Alegre Brazil
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16
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Paul MJ, Probst CK, Brown LM, de Vries GJ. Dissociation of Puberty and Adolescent Social Development in a Seasonally Breeding Species. Curr Biol 2018; 28:1116-1123.e2. [PMID: 29551412 DOI: 10.1016/j.cub.2018.02.030] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2017] [Revised: 02/12/2018] [Accepted: 02/14/2018] [Indexed: 01/09/2023]
Abstract
Alongside the development of sexual characteristics and reproductive competence, adolescents undergo marked cognitive, social, and emotional development [1]. A fundamental question is whether these changes are triggered by activation of the hypothalamic-pituitary-gonadal (HPG) axis at puberty (puberty dependent) or whether they occur independently of HPG activation (puberty independent). Disentangling puberty-dependent from puberty-independent mechanisms is difficult because puberty and adolescence typically proceed concurrently. Here, we test a new approach that leverages natural adaptations of a seasonally breeding species to dissociate pubertal status from chronological age. Siberian hamsters (Phodopus sungorus) reared in a long, summer-like day length (LD) exhibit rapid pubertal development, whereas those reared in a short, winter-like day length (SD) delay puberty by several months to synchronize breeding with the following spring [2, 3]. We tested whether the SD-induced delay in puberty delays the peri-adolescent decline in juvenile social play and the rise in aggression that characterizes adolescent social development in many species [4-6] and compared the results to those obtained after prepubertal gonadectomy. Neither SD rearing nor prepubertal gonadectomy altered the age at which hamsters transitioned from play to aggression; SD-reared hamsters completed this transition prior to puberty. SD rearing and prepubertal gonadectomy, however, increased levels of play in male and female juveniles, implicating a previously unknown role for prepubertal gonadal hormones in juvenile social behavior. Levels of aggression were also impacted (decreased) in SD-reared and gonadectomized males. These data demonstrate that puberty-independent mechanisms regulate the timing of adolescent social development, while prepubertal and adult gonadal hormones modulate levels of age-appropriate social behaviors.
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Affiliation(s)
- Matthew J Paul
- Department of Psychology, University at Buffalo, SUNY, Buffalo, NY 14260, USA; Center for Neuroendocrine Studies, University of Massachusetts, Amherst, Amherst, MA 01003, USA.
| | - Clemens K Probst
- Center for Neuroendocrine Studies, University of Massachusetts, Amherst, Amherst, MA 01003, USA
| | - Lauren M Brown
- Department of Psychology, University at Buffalo, SUNY, Buffalo, NY 14260, USA
| | - Geert J de Vries
- Center for Neuroendocrine Studies, University of Massachusetts, Amherst, Amherst, MA 01003, USA; Neuroscience Institute, Georgia State University, Atlanta, GA 30302, USA
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17
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Cao J, Willett JA, Dorris DM, Meitzen J. Sex Differences in Medium Spiny Neuron Excitability and Glutamatergic Synaptic Input: Heterogeneity Across Striatal Regions and Evidence for Estradiol-Dependent Sexual Differentiation. Front Endocrinol (Lausanne) 2018; 9:173. [PMID: 29720962 PMCID: PMC5915472 DOI: 10.3389/fendo.2018.00173] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/19/2017] [Accepted: 04/03/2018] [Indexed: 12/21/2022] Open
Abstract
Steroid sex hormones and biological sex influence how the brain regulates motivated behavior, reward, and sensorimotor function in both normal and pathological contexts. Investigations into the underlying neural mechanisms have targeted the striatal brain regions, including the caudate-putamen, nucleus accumbens core (AcbC), and shell. These brain regions are of particular interest to neuroendocrinologists given that they express membrane-associated but not nuclear estrogen receptors, and also the well-established role of the sex steroid hormone 17β-estradiol (estradiol) in modulating striatal dopamine systems. Indeed, output neurons of the striatum, the medium spiny neurons (MSNs), exhibit estradiol sensitivity and sex differences in electrophysiological properties. Here, we review sex differences in rat MSN glutamatergic synaptic input and intrinsic excitability across striatal regions, including evidence for estradiol-mediated sexual differentiation in the nucleus AcbC. In prepubertal animals, female MSNs in the caudate-putamen exhibit a greater intrinsic excitability relative to male MSNs, but no sex differences are detected in excitatory synaptic input. Alternatively, female MSNs in the nucleus AcbC exhibit increased excitatory synaptic input relative to male MSNs, but no sex differences in intrinsic excitability were detected. Increased excitatory synaptic input onto female MSNs in the nucleus AcbC is abolished after masculinizing estradiol or testosterone exposure during the neonatal critical period. No sex differences are detected in MSNs in prepubertal nucleus accumbens shell. Thus, despite possessing the same neuron type, striatal regions exhibit heterogeneity in sex differences in MSN electrophysiological properties, which likely contribute to the sex differences observed in striatal function.
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Affiliation(s)
- Jinyan Cao
- Department of Biological Sciences, North Carolina State University, Raleigh, NC, United States
- W.M. Keck Center for Behavioral Biology, North Carolina State University, Raleigh, NC, United States
| | - Jaime A. Willett
- Department of Biological Sciences, North Carolina State University, Raleigh, NC, United States
- W.M. Keck Center for Behavioral Biology, North Carolina State University, Raleigh, NC, United States
- Graduate Program in Physiology, North Carolina State University, Raleigh, NC, United States
| | - David M. Dorris
- Department of Biological Sciences, North Carolina State University, Raleigh, NC, United States
| | - John Meitzen
- Department of Biological Sciences, North Carolina State University, Raleigh, NC, United States
- W.M. Keck Center for Behavioral Biology, North Carolina State University, Raleigh, NC, United States
- Center for Human Health and the Environment, North Carolina State University, Raleigh, NC, United States
- Comparative Medicine Institute, North Carolina State University, Raleigh, NC, United States
- *Correspondence: John Meitzen,
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18
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Magalhães Horn ÂC, Rasia-Filho AA. The Cytoarchitecture of the Telencephalon of Betta Splendens Regan 1910 (Perciformes: Anabantoidei) with a Stereological Approach to the Supracommissural and Postcommissural Nuclei. Anat Rec (Hoboken) 2017; 301:88-110. [PMID: 29024431 DOI: 10.1002/ar.23699] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2016] [Revised: 05/22/2017] [Accepted: 07/13/2017] [Indexed: 11/06/2022]
Abstract
Teleostean fish brains are useful models to study cellular and functional specializations along the phylogenesis. The Betta splendens Regan 1910 (Siamese fighting fish; Perciformes:Anabantoidei) is known for its aggressive display, courtship behavior, nest building, and offspring care. Here, we present novel and detailed data about the cytoarchitecture of the olfactory bulb and the telencephalic hemispheres of this fish. The hematoxylin-eosin and Nissl techniques served to identify brain nuclei (n = 19 males and n = 21 females) and for the stereological evaluation of the numerical density of cells and the proportion of neurons and glial cells in the ventral telencephalon supracommissural (Vs) and postcommissural (Vp) nuclei of adult males and females. These nuclei are putative homologs of the sexually dimorphic medial amygdala in mammals. The olfactory bulb of Betta splendens consists of 5 concentrically arranged layers plus ganglion cells of the terminal nerves. The dorsal telencephalon consists of 16 different cell groups. The ventral telencephalon has 8 nuclei, plus the lateral septal organ and the nuclei of the preoptic area forming an anatomical continuum. The rostrocaudal extent of the Vs and Vp is not different between sexes. In both nuclei, the proportion of neurons to glial cells is approximately 2:1 and the density of neurons and glial cells is not different between sexes. These morphological findings can subserve future research on the brain function of the Betta splendens and the search for neural sex differences in other central areas of this same species, in other teleost species, or yet in other related vertebrate group. Anat Rec, 00:000-000, 2017. © 2017 Wiley Periodicals, Inc. Anat Rec, 301:88-110, 2018. © 2017 Wiley Periodicals, Inc.
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Affiliation(s)
- Ângelo Cássio Magalhães Horn
- Laboratory of Histology, Instituto Federal de Educação, Ciência e Tecnologia do Rio Grande do Sul - Campus Porto Alegre, Porto Alegre, RS 90030-041, Brazil.,ICBS/Neuroscience Program, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS 90050-170, Brazil
| | - Alberto A Rasia-Filho
- ICBS/Neuroscience Program, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS 90050-170, Brazil.,DCBS/Physiology, Universidade Federal de Ciência da Saúde de Porto Alegre, Porto Alegre, RS 90050-170, Brazil
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19
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Sex- and Estrus-Dependent Differences in Rat Basolateral Amygdala. J Neurosci 2017; 37:10567-10586. [PMID: 28954870 DOI: 10.1523/jneurosci.0758-17.2017] [Citation(s) in RCA: 110] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2017] [Revised: 09/18/2017] [Accepted: 09/19/2017] [Indexed: 01/24/2023] Open
Abstract
Depression and anxiety are diagnosed almost twice as often in women, and the symptomology differs in men and women and is sensitive to sex hormones. The basolateral amygdala (BLA) contributes to emotion-related behaviors that differ between males and females and across the reproductive cycle. This hints at sex- or estrus-dependent features of BLA function, about which very little is known. The purpose of this study was to test whether there are sex differences or estrous cyclicity in rat BLA physiology and to determine their mechanistic correlates. We found substantial sex differences in the activity of neurons in lateral nuclei (LAT) and basal nuclei (BA) of the BLA that were associated with greater excitatory synaptic input in females. We also found strong differences in the activity of LAT and BA neurons across the estrous cycle. These differences were associated with a shift in the inhibition-excitation balance such that LAT had relatively greater inhibition during proestrus which paralleled more rapid cued fear extinction. In contrast, BA had relatively greater inhibition during diestrus that paralleled more rapid contextual fear extinction. These results are the first to demonstrate sex differences in BLA neuronal activity and the impact of estrous cyclicity on these measures. The shift between LAT and BA predominance across the estrous cycle provides a simple construct for understanding the effects of the estrous cycle on BLA-dependent behaviors. These results provide a novel framework to understand the cyclicity of emotional memory and highlight the importance of considering ovarian cycle when studying the BLA of females.SIGNIFICANCE STATEMENT There are differences in emotional responses and many psychiatric symptoms between males and females. This may point to sex differences in limbic brain regions. Here we demonstrate sex differences in neuronal activity in one key limbic region, the basolateral amygdala (BLA), whose activity fluctuates across the estrous cycle due to a shift in the balance of inhibition and excitation across two BLA regions, the lateral and basal nuclei. By uncovering this push-pull shift between lateral and basal nuclei, these results help to explain disparate findings about the effects of biological sex and estrous cyclicity on emotion and provide a framework for understanding fluctuations in emotional memory and psychiatric symptoms.
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20
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Burke AR, McCormick CM, Pellis SM, Lukkes JL. Impact of adolescent social experiences on behavior and neural circuits implicated in mental illnesses. Neurosci Biobehav Rev 2017; 76:280-300. [DOI: 10.1016/j.neubiorev.2017.01.018] [Citation(s) in RCA: 123] [Impact Index Per Article: 17.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2016] [Revised: 11/11/2016] [Accepted: 01/06/2017] [Indexed: 12/18/2022]
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21
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Zancan M, Dall'Oglio A, Quagliotto E, Rasia‐Filho AA. Castration alters the number and structure of dendritic spines in the male posterodorsal medial amygdala. Eur J Neurosci 2016; 45:572-580. [DOI: 10.1111/ejn.13460] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2016] [Revised: 10/22/2016] [Accepted: 10/31/2016] [Indexed: 01/21/2023]
Affiliation(s)
- Mariana Zancan
- Department of Basic Sciences/Physiology Federal University of Health Sciences Sarmento Leite 245 Porto Alegre RS 90050‐170 Brazil
- Graduation Program in Neuroscience Federal University of Rio Grande do Sul Porto Alegre Brazil
| | - Aline Dall'Oglio
- Department of Basic Sciences/Physiology Federal University of Health Sciences Sarmento Leite 245 Porto Alegre RS 90050‐170 Brazil
| | - Edson Quagliotto
- Department of Basic Sciences/Physiology Federal University of Health Sciences Sarmento Leite 245 Porto Alegre RS 90050‐170 Brazil
| | - Alberto A. Rasia‐Filho
- Department of Basic Sciences/Physiology Federal University of Health Sciences Sarmento Leite 245 Porto Alegre RS 90050‐170 Brazil
- Graduation Program in Neuroscience Federal University of Rio Grande do Sul Porto Alegre Brazil
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22
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Drzewiecki CM, Willing J, Juraska JM. Synaptic number changes in the medial prefrontal cortex across adolescence in male and female rats: A role for pubertal onset. Synapse 2016; 70:361-8. [PMID: 27103097 DOI: 10.1002/syn.21909] [Citation(s) in RCA: 120] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2015] [Revised: 03/30/2016] [Accepted: 04/19/2016] [Indexed: 12/24/2022]
Abstract
Adolescence is a unique period of development, marked by maturation of the prefrontal cortex (PFC), a region important for executive functioning. During this time, the human PFC decreases in overall volume and thickness. Likewise in adolescent rodents, losses of neurons, dendrites, dendritic spines and neurotransmitter receptors have been documented within the medial prefrontal cortex (mPFC), sometimes with sex and layer specificity. However, changes in the number of synapses during this time have not been examined. In the present study, we stereologically quantified the number of synaptophysin-immunoreactive boutons in the male and female rat mPFC across multiple time points from the juvenile period through adulthood (postnatal days (P) 25, 35, 45, 60 and 90). In females, there was a significant decrease in synaptophysin boutons between P35 and P45, coinciding with the onset of puberty. In males, there was no significant main effect of age on synaptophysin boutons; however, in both males and females, pubertal onset was associated with significant synaptic losses. These results suggest that puberty is a critical period for synaptic pruning within the rat mPFC, potentially contributing to maturation of adolescent executive function. Synapse 70:361-368, 2016. © 2016 Wiley Periodicals, Inc.
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Affiliation(s)
- Carly M Drzewiecki
- Program in Neuroscience, University of Illinois at Urbana-Champaign, Champaign, Illinois, 61820
| | - Jari Willing
- Department of Psychology, University of Illinois at Urbana-Champaign, 603 E Daniel St, Champaign, Illinois, 61820
| | - Janice M Juraska
- Program in Neuroscience, University of Illinois at Urbana-Champaign, Champaign, Illinois, 61820.,Department of Psychology, University of Illinois at Urbana-Champaign, 603 E Daniel St, Champaign, Illinois, 61820
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23
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Hammerslag LR, Gulley JM. Sex differences in behavior and neural development and their role in adolescent vulnerability to substance use. Behav Brain Res 2016; 298:15-26. [PMID: 25882721 PMCID: PMC4603997 DOI: 10.1016/j.bbr.2015.04.008] [Citation(s) in RCA: 65] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2015] [Revised: 04/03/2015] [Accepted: 04/04/2015] [Indexed: 12/18/2022]
Abstract
Adolescents are especially prone to risky behavior and to the emergence of psychological disorders like substance abuse, anxiety and depression. However, there is a sex (or gender) difference in this vulnerability, with females being more prone to developing internalizing disorders and males being more likely to engage in risky behavior and drug use. While several researchers have proposed that there is a relationship between corticolimbic circuit development and adolescent vulnerability, the current proposed models do not take sex differences into account. In this review, we explore recent findings from both human and rodent studies of sex differences during adolescence. In particular, we consider epidemiological studies on the factors that contribute to the development of substance abuse and internalizing disorders, laboratory studies on reward-related and decision-making behavior, and neuroanatomical studies on the development of several structures in the corticolimbic circuit (i.e., prefrontal cortex [PFC], amygdala and striatum). We then integrate these recent findings into models of adolescent vulnerability to substance use that have previously not addressed sex differences. Lastly, we discuss methodological considerations for the interpretation and design of studies on sex (or gender) differences during adolescence while highlighting some opportunities for future investigations.
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Affiliation(s)
| | - Joshua M Gulley
- Neuroscience Program, University of Illinois, Urbana-Champaign, USA; Department of Psychology University of Illinois, Urbana-Champaign, USA.
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24
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Bell MR, Thompson LM, Rodriguez K, Gore AC. Two-hit exposure to polychlorinated biphenyls at gestational and juvenile life stages: 1. Sexually dimorphic effects on social and anxiety-like behaviors. Horm Behav 2016; 78:168-77. [PMID: 26592453 PMCID: PMC4718783 DOI: 10.1016/j.yhbeh.2015.11.007] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/24/2015] [Revised: 11/09/2015] [Accepted: 11/20/2015] [Indexed: 11/17/2022]
Abstract
Endocrine disrupting chemicals (EDCs) are widespread environmental contaminants that affect many neuroendocrine functions. The brain is particularly vulnerable to EDCs during critical periods of gestational development when gonadal hormones exert organizational effects on sexually dimorphic behaviors later in life. Peripubertal development is also a time of continued neural sensitivity to organizing effects of hormones, yet little is known about EDC actions at these times. We sought to determine effects of prenatal or juvenile exposures to a class of EDCs, polychlorinated biphenyls (PCBs) at human-relevant dosages on development, physiology, and social and anxiety-related behaviors later in life, and the consequences of a second juvenile "hit" following prenatal treatment. We exposed male and female Sprague-Dawley rats to PCBs (Aroclor 1221, 1mg/kg/day, ip injection) and/or vehicle during prenatal development (embryonic days 16, 18, 20), juvenile development (postnatal days 24, 26, 28), or both. These exposures had differential effects on behaviors in sex and age-dependent ways; while prenatal exposure had more effects than juvenile, juvenile exposure often modified or unmasked the effects of the first hit. Additionally, females exhibited altered social and anxiety behavior in adolescence, while males displayed small but significant changes in sociosexual preferences in adulthood. Thus, the brain continues to be sensitive to organizing effects of EDCs through juvenile development. As humans are exposed to EDCs throughout multiple periods in their life, these findings have implications for our understanding of EDC effects on physiology and behavior.
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Affiliation(s)
- Margaret R Bell
- Division of Pharmacology and Toxicology, College of Pharmacy, The University of Texas at Austin, Austin, TX 78712, USA
| | - Lindsay M Thompson
- Division of Pharmacology and Toxicology, College of Pharmacy, The University of Texas at Austin, Austin, TX 78712, USA
| | - Karla Rodriguez
- Division of Pharmacology and Toxicology, College of Pharmacy, The University of Texas at Austin, Austin, TX 78712, USA; Franklin College, Franklin, IN 46131, USA
| | - Andrea C Gore
- Division of Pharmacology and Toxicology, College of Pharmacy, The University of Texas at Austin, Austin, TX 78712, USA; Institute for Cellular and Molecular Biology, The University of Texas at Austin, Austin, TX 78712, USA; Institute for Neuroscience, The University of Texas at Austin, Austin, TX 78712, USA.
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25
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Li XF, Hu MH, Hanley BP, Lin YS, Poston L, Lightman SL, O'Byrne KT. The Posterodorsal Medial Amygdala Regulates the Timing of Puberty Onset in Female Rats. Endocrinology 2015; 156:3725-36. [PMID: 26252061 PMCID: PMC4588820 DOI: 10.1210/en.2015-1366] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/04/2022]
Abstract
Obesity is the major risk factor for early puberty, but emerging evidence indicates other factors including psychosocial stress. One key brain region notable for its role in controlling calorie intake, stress, and behavior is the amygdala. Early studies involving amygdala lesions that included the medial nucleus advanced puberty in rats. More recently it was shown that a critical site for lesion-induced hyperphagia and obesity is the posterodorsal subnucleus of the medial amygdala (MePD), which may explain the advancement of puberty. Glutamatergic activity also increases in the MePD during puberty without a corresponding γ-aminobutyric acid (GABA)ergic change, suggesting an overall activation of this brain region. In the present study, we report that neurotoxic lesioning of the MePD advances puberty and increases weight gain in female rats fed a normal diet. However, MePD lesioned rats fed a 25% nonnutritive bulk diet also showed the dramatic advancement of puberty but without the increase in body weight. In both dietary groups, MePD lesions resulted in an increase in socialization and a decrease in play fighting behavior. Chronic GABAA receptor antagonism in the MePD from postnatal day 21 for 14 days also advanced puberty, increased socialization, and decreased play fighting without altering body weight, whereas glutamate receptor antagonism delayed puberty and decreased socialization without affecting play fighting. In conclusion, our results suggest the MePD regulates the timing of puberty via a novel mechanism independent of change in body weight and caloric intake. MePD glutamatergic systems advance the timing of puberty whereas local GABAergic activation results in a delay.
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Affiliation(s)
- X F Li
- Division of Women's Health (X.F.L., M.H.L., B.P.H., Y.S.L., L.P., K.T.O.), Faculty of Life Sciences and Medicine, King's College London, Guy's Campus, London SE1 1UL, United Kingdom; and Henry Wellcome Laboratory for Integrative Neuroscience and Endocrinology (S.L.L.), University of Bristol, Bristol BS1 3NY, United Kingdom
| | - M H Hu
- Division of Women's Health (X.F.L., M.H.L., B.P.H., Y.S.L., L.P., K.T.O.), Faculty of Life Sciences and Medicine, King's College London, Guy's Campus, London SE1 1UL, United Kingdom; and Henry Wellcome Laboratory for Integrative Neuroscience and Endocrinology (S.L.L.), University of Bristol, Bristol BS1 3NY, United Kingdom
| | - B P Hanley
- Division of Women's Health (X.F.L., M.H.L., B.P.H., Y.S.L., L.P., K.T.O.), Faculty of Life Sciences and Medicine, King's College London, Guy's Campus, London SE1 1UL, United Kingdom; and Henry Wellcome Laboratory for Integrative Neuroscience and Endocrinology (S.L.L.), University of Bristol, Bristol BS1 3NY, United Kingdom
| | - Y S Lin
- Division of Women's Health (X.F.L., M.H.L., B.P.H., Y.S.L., L.P., K.T.O.), Faculty of Life Sciences and Medicine, King's College London, Guy's Campus, London SE1 1UL, United Kingdom; and Henry Wellcome Laboratory for Integrative Neuroscience and Endocrinology (S.L.L.), University of Bristol, Bristol BS1 3NY, United Kingdom
| | - L Poston
- Division of Women's Health (X.F.L., M.H.L., B.P.H., Y.S.L., L.P., K.T.O.), Faculty of Life Sciences and Medicine, King's College London, Guy's Campus, London SE1 1UL, United Kingdom; and Henry Wellcome Laboratory for Integrative Neuroscience and Endocrinology (S.L.L.), University of Bristol, Bristol BS1 3NY, United Kingdom
| | - S L Lightman
- Division of Women's Health (X.F.L., M.H.L., B.P.H., Y.S.L., L.P., K.T.O.), Faculty of Life Sciences and Medicine, King's College London, Guy's Campus, London SE1 1UL, United Kingdom; and Henry Wellcome Laboratory for Integrative Neuroscience and Endocrinology (S.L.L.), University of Bristol, Bristol BS1 3NY, United Kingdom
| | - K T O'Byrne
- Division of Women's Health (X.F.L., M.H.L., B.P.H., Y.S.L., L.P., K.T.O.), Faculty of Life Sciences and Medicine, King's College London, Guy's Campus, London SE1 1UL, United Kingdom; and Henry Wellcome Laboratory for Integrative Neuroscience and Endocrinology (S.L.L.), University of Bristol, Bristol BS1 3NY, United Kingdom
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26
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Job MO, Cooke BM. PSA-NCAM in the posterodorsal medial amygdala is necessary for the pubertal emergence of attraction to female odors in male hamsters. Horm Behav 2015; 75:91-9. [PMID: 26335887 DOI: 10.1016/j.yhbeh.2015.08.009] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/03/2015] [Revised: 08/19/2015] [Accepted: 08/22/2015] [Indexed: 10/23/2022]
Abstract
During puberty, attention turns away from same-sex socialization to focus on the opposite sex. How the brain mediates this change in perception and motivation is unknown. Polysialylated neural cell adhesion molecule (PSA-NCAM) virtually disappears from most of the central nervous system after embryogenesis, but it remains elevated in discrete regions of the adult brain. One such brain area is the posterodorsal subnucleus of the medial amygdala (MePD). The MePD has been implicated in male sexual attraction, measured here as the preference to investigate female odors. We hypothesize that PSA-NCAM gates hormone-dependent plasticity necessary for the emergence of males' attraction to females. To evaluate this idea, we first measured PSA-NCAM levels across puberty in several brain regions, and identified when female odor preference normally emerges in male Syrian hamsters. We found that MePD PSA-NCAM staining peaks shortly before the surge of pubertal androgen and the emergence of preference. To test the necessity of PSA-NCAM for female odor preference, we infused endo-neuraminidase-N into the MePD to deplete it of PSAs before female odor preference normally appears. This blocked female odor preference, which suggests that PSA-NCAM facilitates behaviorally relevant, hormone-driven plasticity.
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Affiliation(s)
- Martin O Job
- Neuroscience Institute, Georgia State University, Atlanta, GA 30303, USA
| | - Bradley M Cooke
- Neuroscience Institute, Georgia State University, Atlanta, GA 30303, USA.
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Koss WA, Lloyd MM, Sadowski RN, Wise LM, Juraska JM. Gonadectomy before puberty increases the number of neurons and glia in the medial prefrontal cortex of female, but not male, rats. Dev Psychobiol 2015; 57:305-12. [PMID: 25782706 DOI: 10.1002/dev.21290] [Citation(s) in RCA: 66] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2014] [Accepted: 01/05/2015] [Indexed: 12/28/2022]
Abstract
The human prefrontal cortex, important for executive functions, loses gray matter throughout the adolescent period. In rats, our laboratory demonstrated that a loss of neurons between adolescence and adulthood partially underlies the loss of volume, and this loss is greater in females than males. Here, we examine whether being deprived of gonadal hormones before puberty through adulthood influences the number of neurons in the medial prefrontal cortex (mPFC). Prior to puberty, the testes or ovaries were removed in male and female rats. In adulthood, the number of neurons and glia in the mPFC were quantified using unbiased stereology, and the volume of the frontal white matter was measured. Prepubertal ovariectomy resulted in a higher number of neurons and glia and a larger volume of white matter compared to sham control littermates. Castrated males were not different from sham males on any measure. Thus ovarian hormones secreted after puberty influence the cellular composition of the medial prefrontal cortex.
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Affiliation(s)
- Wendy A Koss
- Department of Psychology, University of Illinois, Champaign, 61820, IL
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28
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Brusco J, Merlo S, Ikeda ÉT, Petralia RS, Kachar B, Rasia-Filho AA, Moreira JE. Inhibitory and multisynaptic spines, and hemispherical synaptic specialization in the posterodorsal medial amygdala of male and female rats. J Comp Neurol 2015; 522:2075-88. [PMID: 24318545 DOI: 10.1002/cne.23518] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2013] [Revised: 11/26/2013] [Accepted: 12/03/2013] [Indexed: 12/23/2022]
Abstract
The density of dendritic spines is sexually dimorphic and variable throughout the female estrous cycle in the rat posterodorsal medial amygdala (MePD), a relevant area for the modulation of reproductive behavior in rats. The local synaptic activity differs between hemispheres in prepubertal animals. Here we used serial section transmission electron microscopy to produce 3D reconstructions of dendritic shafts and spines to characterize synaptic contacts on MePD neurons of both hemispheres in adult males and in females along the estrous cycle. Pleomorphic spines and nonsynaptic filopodia occur in the MePD. On average, 8.6% of dendritic spines received inputs from symmetric gamma-aminobutyric acid (GABA)-immunoreactive terminals, whereas 3.6% received two synaptic contacts on the spine head, neck, or base. Presynaptic terminals in female right MePD had a higher density of synaptic vesicles and docked vesicles than the left MePD, suggesting a higher rate of synaptic vesicle release in the right MePD of female rats. In contrast, males did not show laterality in any of those parameters. The proportion of putative inhibitory synapses on dendritic shafts in the right MePD of females in proestrus was higher than in the left MePD, and higher than in the right MePD in males, or in females in diestrus or estrus. This work shows synaptic laterality depending on sex and estrous cycle phase in mature MePD neurons. Most likely, sexual hormone effects are lateralized in this brain region, leading to higher synaptic activity in the right than in the left hemisphere of females, mediating timely neuroendocrine and social/reproductive behavior.
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Affiliation(s)
- Janaina Brusco
- Department of Neuroscience and Behavior, University of São Paulo, School of Medicine at Ribeirão Preto, Ribeirão Preto, SP, 14049-900, Brazil; National Institute on Deafness and Other Communication Disorders, National Institutes of Health, Bethesda, MD, 20892, USA
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29
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Dorris DM, Cao J, Willett JA, Hauser CA, Meitzen J. Intrinsic excitability varies by sex in prepubertal striatal medium spiny neurons. J Neurophysiol 2014; 113:720-9. [PMID: 25376786 DOI: 10.1152/jn.00687.2014] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Sex differences in neuron electrophysiological properties were traditionally associated with brain regions directly involved in reproduction in adult, postpubertal animals. There is growing acknowledgement that sex differences can exist in other developmental periods and brain regions as well. This includes the dorsal striatum (caudate/putamen), which shows robust sex differences in gene expression, neuromodulator action (including dopamine and 17β-estradiol), and relevant sensorimotor behaviors and pathologies such as the responsiveness to drugs of abuse. Here we examine whether these sex differences extend to striatal neuron electrophysiology. We test the hypothesis that passive and active medium spiny neuron (MSN) electrophysiological properties in prepubertal rat dorsal striatum differ by sex. We made whole cell recordings from male and females MSNs from acute brain slices. The slope of the evoked firing rate to current injection curve was increased in MSNs recorded from females compared with males. The initial action potential firing rate was increased in MSNs recorded from females compared with males. Action potential after-hyperpolarization peak was decreased, and threshold was hyperpolarized in MSNs recorded from females compared with males. No sex differences in passive electrophysiological properties or miniature excitatory synaptic currents were detected. These findings indicate that MSN excitability is increased in prepubertal females compared with males, providing a new mechanism that potentially contributes to generating sex differences in striatal-mediated processes. Broadly, these findings demonstrate that sex differences in neuron electrophysiological properties can exist prepuberty in brain regions not directly related to reproduction.
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Affiliation(s)
- David M Dorris
- Department of Biological Sciences, North Carolina State University, Raleigh, North Carolina
| | - Jinyan Cao
- Department of Biological Sciences, North Carolina State University, Raleigh, North Carolina; W. M. Keck Center for Behavioral Biology, North Carolina State University, Raleigh, North Carolina
| | - Jaime A Willett
- Department of Biological Sciences, North Carolina State University, Raleigh, North Carolina; W. M. Keck Center for Behavioral Biology, North Carolina State University, Raleigh, North Carolina; Graduate Program in Physiology, North Carolina State University, Raleigh, North Carolina
| | - Caitlin A Hauser
- Department of Biological Sciences, North Carolina State University, Raleigh, North Carolina
| | - John Meitzen
- Department of Biological Sciences, North Carolina State University, Raleigh, North Carolina; W. M. Keck Center for Behavioral Biology, North Carolina State University, Raleigh, North Carolina; Center for Human Health and the Environment, Center for Comparative Medicine and Translational Research, North Carolina State University, Raleigh, North Carolina; and Grass Laboratory, Marine Biological Laboratory, Woods Hole, Massachusetts
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30
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Morales M, Varlinskaya EI, Spear LP. Pre-pubertal gonadectomy and the social consequences of acute ethanol in adolescent male and female rats. Horm Behav 2014; 66:209-19. [PMID: 24816080 PMCID: PMC4127139 DOI: 10.1016/j.yhbeh.2014.04.015] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/28/2014] [Revised: 04/13/2014] [Accepted: 04/29/2014] [Indexed: 10/25/2022]
Abstract
It has previously been shown that pre-pubertal or adult gonadectomy (GX) increases ethanol intake in male rats. This study examined whether this sex-selective increase reflects a GX-induced maintenance in males of more adolescent-typical responsiveness to ethanol characterized by enhanced sensitivity to positive (e.g., socially facilitating) and a decreased sensitivity to adverse (e.g., socially inhibitory) effects of ethanol. Male and female Sprague-Dawley rats were pre-pubertally GX, sham (SH)-operated, or non-manipulated (NM) at postnatal day (P) 25. During the late adolescent transition into adulthood (P48 - baseline day), rats were given a saline injection, placed alone into a familiar test apparatus for 30min and then exposed for 10min to an unfamiliar partner of the same age and sex. On the following day (P49), similar testing occurred after administration of 0.5, 0.75, 1.0 or 1.25g/kg ethanol. At baseline, GX males and females displayed higher levels of social activity (especially adolescent-typical play and contact behavior) than SH and NM animals, with GX females displaying greater social activity than GX males. Neither males nor females demonstrated social facilitation at lower ethanol doses, regardless of hormonal status. Whereas the social inhibitory effects of higher doses of ethanol were similar across groups among females, SH males were less sensitive than both GX and NM males to ethanol-induced social inhibition. These results suggest that enhanced ethanol intake in GX males is not related to alterations in sensitivity to ethanol's social inhibitory effects. GX, however, results in retention of adolescent-typical social behaviors, with older GX adolescent rats resembling early adolescents in exhibiting elevated social activity-particularly play and contact behavior.
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Affiliation(s)
- Melissa Morales
- Center for Development and Behavioral Neuroscience, Department of Psychology, Binghamton University, Binghamton, New York 13902-6000, USA.
| | - Elena I Varlinskaya
- Center for Development and Behavioral Neuroscience, Department of Psychology, Binghamton University, Binghamton, New York 13902-6000, USA
| | - Linda P Spear
- Center for Development and Behavioral Neuroscience, Department of Psychology, Binghamton University, Binghamton, New York 13902-6000, USA
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31
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Nuruddin S, Bruchhage M, Ropstad E, Krogenæs A, Evans NP, Robinson JE, Endestad T, Westlye LT, Madison C, Haraldsen IRH. Effects of peripubertal gonadotropin-releasing hormone agonist on brain development in sheep--a magnetic resonance imaging study. Psychoneuroendocrinology 2013; 38:1994-2002. [PMID: 23579083 DOI: 10.1016/j.psyneuen.2013.03.009] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/07/2012] [Revised: 02/24/2013] [Accepted: 03/09/2013] [Indexed: 12/18/2022]
Abstract
In many species sexual dimorphisms in brain structures and functions have been documented. In ovine model, we have previously demonstrated that peri-pubertal pharmacological blockade of gonadotropin releasing hormone (GnRH) action increased sex-differences of executive emotional behavior. The structural substrate of this behavioral alteration however is unknown. In this magnetic resonance image (MRI) study on the same animals, we investigated the effects of GnRH agonist (GnRHa) treatment on the volume of total brain, hippocampus and amygdala. In total 41 brains (17 treated; 10 females and 7 males, and 24 controls; 11 females and 13 males) were included in the MRI study. Image acquisition was performed with 3-T MRI scanner. Segmentation of the amygdala and the hippocampus was done by manual tracing and total gray and white matter volumes were estimated by means of automated brain volume segmentation of the individual T2-weighted MRI volumes. Statistical comparisons were performed with general linear models. Highly significant GnRHa treatment effects were found on the volume of left and right amygdala, indicating larger amygdalae in treated animals. Significant sex differences were found for total gray matter and right amygdala, indicating larger volumes in male compared to female animals. Additionally, we observed a significant interaction between sex and treatment on left amygdala volume, indicating stronger effects of treatment in female compared to male animals. The effects of GnRHa treatment on amygdala volumes indicate that increasing GnRH concentration during puberty may have an important impact on normal brain development in mammals. These novel findings substantiate the need for further studies investigating potential neurobiological side effects of GnRHa treatment on the brains of young animals and humans.
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Affiliation(s)
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- Norwegian School of Veterinary Science, PB 8146 Dep, 0033 Oslo, Norway
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32
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Varlinskaya EI, Vetter-O'Hagen CS, Spear LP. Puberty and gonadal hormones: role in adolescent-typical behavioral alterations. Horm Behav 2013; 64:343-9. [PMID: 23998677 PMCID: PMC3761212 DOI: 10.1016/j.yhbeh.2012.11.012] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/01/2012] [Revised: 10/30/2012] [Accepted: 11/14/2012] [Indexed: 11/22/2022]
Abstract
This article is part of a Special Issue "Puberty and Adolescence". Adolescence is characterized by a variety of behavioral alterations, including elevations in novelty-seeking and experimentation with alcohol and other drugs of abuse. Some adolescent-typical neurobehavioral alterations may depend upon pubertal rises in gonadal hormones, whereas others may be unrelated to puberty. Using a variety of approaches, studies in laboratory animals have not revealed clear relationships between pubertal-related changes and adolescent- or adult-typical behaviors that are not strongly sexually dimorphic. Data reviewed suggest surprisingly modest influences of gonadal hormones on alcohol intake, alcohol preference and novelty-directed behaviors. Gonadectomy in males (but not females) increased ethanol intake in adulthood following surgery either pre-pubertally or in adulthood, with these increases in intake largely reversed by testosterone replacement in adulthood, supporting an activational role of androgens in moderating ethanol intake in males. In contrast, neither pre-pubertal nor adult gonadectomy influenced sensitivity to the social inhibitory or aversive effects of ethanol when indexed via conditioned taste aversions, although gonadectomy at either age altered the microstructure of social behavior of both males and females. Unexpectedly, the pre-pubertal surgical manipulation process itself was found to increase later ethanol intake, decrease sensitivity to ethanol's social inhibitory effects, attenuate novelty-directed behavior and lower social motivation, with gonadal hormones being necessary for these long-lasting effects of early surgical perturbations.
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Affiliation(s)
- Elena I Varlinskaya
- Center for Development and Behavioral Neuroscience, Department of Psychology, Binghamton University, Binghamton, NY 13902-6000, USA.
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33
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Juraska JM, Sisk CL, DonCarlos LL. Sexual differentiation of the adolescent rodent brain: hormonal influences and developmental mechanisms. Horm Behav 2013; 64:203-10. [PMID: 23998664 DOI: 10.1016/j.yhbeh.2013.05.010] [Citation(s) in RCA: 143] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/16/2013] [Revised: 05/03/2013] [Accepted: 05/28/2013] [Indexed: 11/24/2022]
Abstract
This article is part of a Special Issue "Puberty and Adolescence". Sexual differentiation is the process by which the nervous system becomes structurally and functionally dissimilar in females and males. In mammals, this process has been thought to occur during prenatal and early postnatal development, when a transient increase in testosterone secretion masculinizes and defeminizes the developing male nervous system. Decades of research have led to the views that structural sexual dimorphisms created during perinatal development are passively maintained throughout life, and that ovarian hormones do not play an active role in feminization of the nervous system. Furthermore, perinatal testosterone was thought to determine sex differences in neuron number by regulating cell death and cell survival, and not by regulating cell proliferation. As investigations of neural development during adolescence became more prominent in the late 20th century and revealed the extent of brain remodeling during this time, each of these tenets has been challenged and modified. Here we review evidence from the animal literature that 1) the brain is further sexually differentiated during puberty and adolescence; 2) ovarian hormones play an active role in the feminization of the brain during puberty; and 3) hormonally modulated, sex-specific addition of new neurons and glial cells, as well as loss of neurons, contribute to sexual differentiation of hypothalamic, limbic, and cortical regions during adolescence. This architectural remodeling during the adolescent phase of sexual differentiation of the brain may underlie the known sex differences in vulnerability to addiction and psychiatric disorders that emerge during this developmental period.
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Affiliation(s)
- Janice M Juraska
- Department of Psychology and Neuroscience Program, University of Illinois, 603 E Daniel St., Champaign, IL 61820, United States.
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34
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Brown GR, Spencer KA. Steroid hormones, stress and the adolescent brain: a comparative perspective. Neuroscience 2012; 249:115-28. [PMID: 23262238 DOI: 10.1016/j.neuroscience.2012.12.016] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2012] [Revised: 11/30/2012] [Accepted: 12/01/2012] [Indexed: 02/07/2023]
Abstract
Steroid hormones, including those produced by the gonads and the adrenal glands, are known to influence brain development during sensitive periods of life. Until recently, most brain organisation was assumed to take place during early stages of development, with relatively little neurogenesis or brain re-organisation during later stages. However, an increasing body of research has shown that the developing brain is also sensitive to steroid hormone exposure during adolescence (broadly defined as the period from nutritional independence to sexual maturity). In this review, we examine how steroid hormones that are produced by the gonads and adrenal glands vary across the lifespan in a range of mammalian and bird species, and we summarise the evidence that steroid hormone exposure influences behavioural and brain development during early stages of life and during adolescence in these two taxonomic groups. Taking a cross-species, comparative perspective reveals that the effects of early exposure to steroid hormones depend upon the stage of development at birth or hatching, as measured along the altricial-precocial dimension. We then review the evidence that exposure to stress during adolescence impacts upon the developing neuroendocrine systems, the brain and behaviour. Current research suggests that the effects of adolescent stress vary depending upon the sex of the individual and type of stressor, and the effects of stress could involve several neural systems, including the serotonergic and dopaminergic systems. Experience of stressors during adolescence could also influence brain development via the close interactions between the stress hormone and gonadal hormone axes. While sensitivity of the brain to steroid hormones during early life and adolescence potentially leaves the developing organism vulnerable to external adversities, developmental plasticity also provides an opportunity for the developing organism to respond to current circumstances and for behavioural responses to influence the future life history of the individual.
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Affiliation(s)
- G R Brown
- School of Psychology and Neuroscience, University of St Andrews, UK.
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35
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Cooke BM, Shukla D. Double helix: reciprocity between juvenile play and brain development. Dev Cogn Neurosci 2011; 1:459-70. [PMID: 22436567 PMCID: PMC6987541 DOI: 10.1016/j.dcn.2011.07.001] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2011] [Revised: 06/27/2011] [Accepted: 07/03/2011] [Indexed: 01/03/2023] Open
Abstract
This review summarizes what is presently known about the function, sexual differentiation, and neural circuitry of juvenile rough-and-tumble play. Juvenile rough-and-tumble play is a unique motivated behavior that is widespread throughout the mammalian order and usually occurs more often in males. Immediate early gene studies indicate that cortical and subcortical circuits, many of which are sensitive to sex steroid hormones, mediate juvenile play. Sex differences in rough-and-tumble play are controlled in part by neonatal exposure to androgens or their estrogenic metabolites. Studies indicate that testicular androgens during play are also necessary to stimulate male-like levels of play initiation. The resemblance of rough-and-tumble play to aggression and sexual behavior has led some to question whether male-typical adult behavior is contingent upon the experience of play. Attempts to control the amount of play through social isolation show that social experience during adolescence is critical for male-typical adult behaviors to be expressed. This well-established finding, together with evidence that play induces neural plasticity, supports the hypothesis that juvenile play contributes to male-typical brain development that ultimately enables the expression of adult social and reproductive behavior.
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Affiliation(s)
- Bradley M Cooke
- Neuroscience Institute, Georgia State University, Atlanta, GA 30303, United States.
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36
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Ybarra N, Hemond PJ, O'Boyle MP, Suter KJ. Spatially selective, testosterone-independent remodeling of dendrites in gonadotropin-releasing hormone (GnRH) neurons prepubertally in male rats. Endocrinology 2011; 152:2011-9. [PMID: 21343259 PMCID: PMC3075933 DOI: 10.1210/en.2010-0871] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Adult GnRH neurons exhibit a stereotypic morphology with a small soma, single axon, and single dendrite arising from the soma with little branching. The adult morphology of GnRH neurons in mice reflects an anatomical consolidation of dendrites over postnatal development. We examined this issue in rat GnRH neurons with biocytin filling in live hypothalamic slices from infant males, as adult littermates and in gonad-intact males, castrated males, and in males with one of three levels of testosterone (T) treatment. Somatic area and total dendritic length were significantly greater in infant males than in adults. Moreover, total numbers of dendrite branches were greater in infant males as compared with adults. The number of higher order branches and the lengths of higher order branches were also greater in infant males than in adults. Most interestingly, in adults a single dendrite arose from the somata, consistently at 180° from the axon. In contrast, prepubertal animals had an average of 2.2 ± 0.2 primary dendrites arising from somata (range, one to seven primary dendrites). Angles relative to the axon at which dendrites in prepubertal males emanated from GnRH somata were highly variable. Castration at 25 d of age and castration at 25 d of age with one of three levels of T treatment did not influence morphological parameters when GnRH neurons were examined between 40 d and 48 d of age. Thus, a spatially selective remodeling of primary dendrites and consolidation of distal GnRH dendritic arbors occurs during postnatal development and is largely independent of T.
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Affiliation(s)
- Natividad Ybarra
- Department of Biology, University of Texas San Antonio, San Antonio, Texas 78249, USA
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37
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Abstract
The medial amygdala (MeA) is an important site for the gonadal hormone control of several socio-sexual behaviours that emerge during puberty, including aggression, mating and parental behaviour. We have previously shown that rising levels of pubertal androgens increase the regional volume and mean soma size of neurones in the posterodorsal subnucleus of the MeA, the MePD. The present study aimed to determine some of the constituents of pubertal volumetric growth. Using computer-guided unbiased stereology, we compared the regional volume, mean somal volume and the overall number of neurones and glia in 45-day-old male Siberian hamsters (Phodopus sungorus). Half of the hamsters had completed puberty, whereas the remainder were prepubertal as a result of photoinhibition of the hypothalamic-pituitary-gonadal axis. Puberty significantly increased MePD regional volume and mean somal volume, as previously observed. We also compared the number of puncta immunoreactive for vesicular glutamate transporter-2 (vGlut2) and post-synaptic density 95 (PSD-95), which are both markers of glutamatergic pre- and post-synaptic specialisations, as well as glutamic acid decarboxylase 65 (GAD-65), which is a marker of GABAergic terminals. Puberty increased the number of vGlut2 and PSD-95 immunoreactive puncta by two- and three-fold, respectively, whereas the number of GAD-65 immunoreactive puncta was unchanged. These results suggest that numerous excitatory synapses are added to the MeA during puberty. More broadly, they show that the pubertal emergence of sexual behaviour is accompanied by synaptic reorganisation of a key network involved in the expression of sexual behaviour.
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Affiliation(s)
- B M Cooke
- Neuroscience Intitute, Georgia State University, Atlanta, GA 30303, USA.
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Sex difference in cell proliferation in developing rat amygdala mediated by endocannabinoids has implications for social behavior. Proc Natl Acad Sci U S A 2010; 107:20535-40. [PMID: 21059913 DOI: 10.1073/pnas.1005003107] [Citation(s) in RCA: 74] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The amygdala is a sexually dimorphic brain region critical for the regulation of social, cognitive, and emotional behaviors, but both the nature and the source of sex differences in the amygdala are largely unknown. We have identified a unique sex difference in the developing rat medial amygdala (MeA) that is regulated by cannabinoids. Newborn females had higher rates of cell proliferation than males. Treatment of neonates with the cannabinoid receptor agonist, WIN 55,212-2 (WIN), reduced cell proliferation in females to that of males and a wide range of WIN doses had no effect on cell proliferation in males. The effect of WIN on cell proliferation in the MeA was prevented by coinfusions of a CB2 but not CB1 receptor antagonist. Females had higher amygdala content of the endocannabinoid degradation enzymes, fatty acid amid hydrolase, and monoacylglycerol lipase than males, and lower amounts of the endocannabinoids 2-arachidonoylglycerol and N-arachidonylethanolamide (anandamide). Inhibition of the degradation of 2-arachidonoylglycerol in females occluded the sex difference in cell proliferation. Analyses of cell fate revealed that females had significantly more newly generated glial cells but not more newly generated neurons than males, and treatment with WIN significantly decreased glial cell genesis in females but not males. Finally, early exposure to cannabinoids masculinized juvenile play behavior in females but did not alter this behavior in males. Collectively, our findings suggest that sex differences in endocannabinoids mediate a sex difference in glial cell genesis in the developing MeA that impacts sex-specific behaviors in adolescence.
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Descriptive findings on the morphology of dendritic spines in the rat medial amygdala. Neurosci Lett 2010; 483:152-6. [DOI: 10.1016/j.neulet.2010.07.083] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2010] [Revised: 07/23/2010] [Accepted: 07/28/2010] [Indexed: 12/16/2022]
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Adolescent development, hypothalamic-pituitary-adrenal function, and programming of adult learning and memory. Prog Neuropsychopharmacol Biol Psychiatry 2010; 34:756-65. [PMID: 19782715 DOI: 10.1016/j.pnpbp.2009.09.019] [Citation(s) in RCA: 165] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/14/2009] [Revised: 09/08/2009] [Accepted: 09/16/2009] [Indexed: 01/20/2023]
Abstract
Chronic exposure to stress is known to affect learning and memory in adults through the release of glucocorticoid hormones by the hypothalamic-pituitary-adrenal (HPA) axis. In adults, glucocorticoids alter synaptic structure and function in brain regions that express high levels of glucocorticoid receptors and that mediate goal-directed behaviour and learning and memory. In contrast to relatively transient effects of stress on cognitive function in adulthood, exposure to high levels of glucocorticoids in early life can produce enduring changes through substantial remodeling of the developing nervous system. Adolescence is another time of significant brain development and maturation of the HPA axis, thereby providing another opportunity for glucocorticoids to exert programming effects on neurocircuitry involved in learning and memory. These topics are reviewed, as is the emerging research evidence in rodent models highlighting that adolescence may be a period of increased vulnerability compared to adulthood in which exposure to high levels of glucocorticoids results in enduring changes in adult cognitive function.
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Arpini M, Menezes IC, Dall’Oglio A, Rasia-Filho AA. The density of Golgi-impregnated dendritic spines from adult rat posterodorsal medial amygdala neurons displays no evidence of hemispheric or dorsal/ventral differences. Neurosci Lett 2010; 469:209-13. [DOI: 10.1016/j.neulet.2009.11.076] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2009] [Revised: 11/24/2009] [Accepted: 11/25/2009] [Indexed: 12/27/2022]
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Sex differences in NADPH-diaphorase activity in the rat posterodorsal medial amygdala. Brain Res 2009; 1305:31-9. [DOI: 10.1016/j.brainres.2009.09.110] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2009] [Revised: 09/28/2009] [Accepted: 09/28/2009] [Indexed: 02/06/2023]
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