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Kaul D, Smith CC, Stevens J, Fröhlich AS, Binder EB, Mechawar N, Schwab SG, Matosin N. Severe childhood and adulthood stress associates with neocortical layer-specific reductions of mature spines in psychiatric disorders. Neurobiol Stress 2020; 13:100270. [PMID: 33344723 PMCID: PMC7739192 DOI: 10.1016/j.ynstr.2020.100270] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2020] [Revised: 11/04/2020] [Accepted: 11/17/2020] [Indexed: 12/22/2022] Open
Abstract
Severe stress exposure causes the loss of dendritic spines on cortical pyramidal neurons and induces psychiatric-like symptoms in rodent models. These effects are strongest following early-life stress and are most persistent on apical dendrites. However, the long-term impacts and temporal effects of stress exposure on the human brain remain poorly understood. Using a novel postmortem cohort of psychiatric cases with severe stress experienced in childhood, adulthood, or no severe stress, and matched controls, we aimed to determine the impact of stress timing on pyramidal neuron structure in the human orbitofrontal cortex (OFC). We performed Golgi Cox staining and manually measured the morphology and density of over 22,000 dendritic spines on layer-specific pyramidal neuron apical dendrites. We also quantified glucocorticoid receptor mRNA and protein as a marker of stress dysregulation. Both childhood and adulthood stress were associated with large reductions in mature mushroom spine density (up to 56% loss) in both the superficial (II/III) and deeper layers (V) of the OFC. However, childhood stress caused more substantial reductions to both total and mature mushroom spines. No difference in glucocorticoid receptor mRNA and protein were seen between groups, although both negatively correlated with total spine density within the whole cohort. These findings indicate that severe stress, especially when experienced during childhood, persistently affects the fine morphological properties of neurons in the human OFC. This may impact on cell connectivity in this brain area, and at least partly explain the social and emotional symptoms that originate in the OFC in psychiatric disorders.
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Affiliation(s)
- Dominic Kaul
- Illawarra Health and Medical Research Institute, Northfields Ave, Wollongong, 2522, Australia.,Molecular Horizons, School of Chemistry and Molecular Biosciences, University of Wollongong, Northfields Ave, Wollongong, 2522, Australia
| | - Caine C Smith
- NSW Brain Tissue Resource Centre, Discipline of Pathology, School of Medical Sciences, University of Sydney, Sydney, Australia
| | - Julia Stevens
- NSW Brain Tissue Resource Centre, Discipline of Pathology, School of Medical Sciences, University of Sydney, Sydney, Australia
| | - Anna S Fröhlich
- Dept. of Translational Research in Psychiatry, Max Planck Institute of Psychiatry, Kraepelinstrasse 2-10, 80804, Munich, Germany.,International Max Planck Research School for Translational Psychiatry, Max Planck Institute of Psychiatry, 80804, Munich, Germany
| | - Elisabeth B Binder
- Dept. of Translational Research in Psychiatry, Max Planck Institute of Psychiatry, Kraepelinstrasse 2-10, 80804, Munich, Germany
| | - Naguib Mechawar
- Douglas Mental Health University Institute, 6875 LaSalle Blvd, Verdun, Qc, Canada, H4H 1R3
| | - Sibylle G Schwab
- Illawarra Health and Medical Research Institute, Northfields Ave, Wollongong, 2522, Australia.,Molecular Horizons, School of Chemistry and Molecular Biosciences, University of Wollongong, Northfields Ave, Wollongong, 2522, Australia
| | - Natalie Matosin
- Illawarra Health and Medical Research Institute, Northfields Ave, Wollongong, 2522, Australia.,Molecular Horizons, School of Chemistry and Molecular Biosciences, University of Wollongong, Northfields Ave, Wollongong, 2522, Australia.,Dept. of Translational Research in Psychiatry, Max Planck Institute of Psychiatry, Kraepelinstrasse 2-10, 80804, Munich, Germany
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2
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Taylor MR, Roby CR, Elziny S, Duricy E, Taylor TM, Bowers JM. Age, but Not Sex, Modulates Foxp3 Expression in the Rat Brain across Development. Neuroscience 2020; 442:87-99. [PMID: 32599120 DOI: 10.1016/j.neuroscience.2020.06.032] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2019] [Revised: 06/17/2020] [Accepted: 06/20/2020] [Indexed: 12/18/2022]
Abstract
The interconnectivity between brain development and the immune system has become an area of interest for many neuroscientists. However, to date, a limited number of known immune mediators of the peripheral nervous system (PNS) have been found to influence the development of the central nervous system (CNS). FOXP3 is a well-established mediator of regulatory T-cells in the PNS. However, the expression pattern of FOXP3 in the CNS and the PNS throughout development is unknown. To fill this void, we have characterized, in several brain regions, the developmental profile of Foxp3 for both sexes using rats. We found different patterns of Foxp3 in the CNS and PNS. In the CNS, we found Foxp3 was ubiquitously expressed, with the levels of Foxp3 varying by brain region. We also found both Foxp3 mRNA and protein levels peak during embryonic development and then steadily decrease with a peak increase during adulthood. In adulthood, the protein but not mRNA increases to the equivalent levels found at the embryonic stage of life. In the PNS, Foxp3 protein levels were low embryonically and increased steadily over the life of the animal with maximal levels reached in adulthood. Patterns observed for both the PNS and CNS were similar in males and females across all developmental timepoints. Our novel findings have implications for understanding how the neural immune system impacts neurodevelopmental disorders such as autism and schizophrenia.
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Affiliation(s)
- Makenzlie R Taylor
- School of Neuroscience, 1981 Kraft Drive, ILSB, Virginia Tech, Blacksburg, VA 24061-0913, USA
| | - Clinton R Roby
- School of Neuroscience, 1981 Kraft Drive, ILSB, Virginia Tech, Blacksburg, VA 24061-0913, USA
| | - Soad Elziny
- School of Neuroscience, 1981 Kraft Drive, ILSB, Virginia Tech, Blacksburg, VA 24061-0913, USA
| | - Erin Duricy
- School of Neuroscience, 1981 Kraft Drive, ILSB, Virginia Tech, Blacksburg, VA 24061-0913, USA
| | - Tina M Taylor
- School of Neuroscience, 1981 Kraft Drive, ILSB, Virginia Tech, Blacksburg, VA 24061-0913, USA
| | - J Michael Bowers
- School of Neuroscience, 1981 Kraft Drive, ILSB, Virginia Tech, Blacksburg, VA 24061-0913, USA.
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3
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Carroll L, Braeutigam S, Dawes JM, Krsnik Z, Kostovic I, Coutinho E, Dewing JM, Horton CA, Gomez-Nicola D, Menassa DA. Autism Spectrum Disorders: Multiple Routes to, and Multiple Consequences of, Abnormal Synaptic Function and Connectivity. Neuroscientist 2020; 27:10-29. [PMID: 32441222 PMCID: PMC7804368 DOI: 10.1177/1073858420921378] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Autism spectrum disorders (ASDs) are a heterogeneous group of
neurodevelopmental disorders of genetic and environmental etiologies.
Some ASD cases are syndromic: associated with clinically defined
patterns of somatic abnormalities and a neurobehavioral phenotype
(e.g., Fragile X syndrome). Many cases, however, are idiopathic or
non-syndromic. Such disorders present themselves during the early
postnatal period when language, speech, and personality start to
develop. ASDs manifest by deficits in social communication and
interaction, restricted and repetitive patterns of behavior across
multiple contexts, sensory abnormalities across multiple modalities
and comorbidities, such as epilepsy among many others. ASDs are
disorders of connectivity, as synaptic dysfunction is common to both
syndromic and idiopathic forms. While multiple theories have been
proposed, particularly in idiopathic ASDs, none address why certain
brain areas (e.g., frontotemporal) appear more vulnerable than others
or identify factors that may affect phenotypic specificity. In this
hypothesis article, we identify possible routes leading to, and the
consequences of, altered connectivity and review the evidence of
central and peripheral synaptic dysfunction in ASDs. We postulate that
phenotypic specificity could arise from aberrant experience-dependent
plasticity mechanisms in frontal brain areas and peripheral sensory
networks and propose why the vulnerability of these areas could be
part of a model to unify preexisting pathophysiological theories.
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Affiliation(s)
- Liam Carroll
- Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, Oxfordshire, UK
| | - Sven Braeutigam
- Oxford Centre for Human Brain Activity, Wellcome Centre for Integrative Neuroimaging, Department of Psychiatry, University of Oxford, Oxford, Oxfordshire, UK
| | - John M Dawes
- Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, Oxfordshire, UK
| | - Zeljka Krsnik
- Croatian Institute for Brain Research, Centre of Research Excellence for Basic, Clinical and Translational Neuroscience, University of Zagreb School of Medicine, Zagreb, Croatia
| | - Ivica Kostovic
- Croatian Institute for Brain Research, Centre of Research Excellence for Basic, Clinical and Translational Neuroscience, University of Zagreb School of Medicine, Zagreb, Croatia
| | - Ester Coutinho
- Maurice Wohl Clinical Neuroscience Institute, King's College London, London, UK
| | - Jennifer M Dewing
- Faculty of Medicine, University of Southampton, Southampton, Hampshire, UK
| | - Christopher A Horton
- Sir William Dunn School of Pathology, University of Oxford, Oxford, Oxfordshire, UK
| | - Diego Gomez-Nicola
- Biological Sciences, Faculty of Environmental and Life Sciences, University of Southampton, Southampton, UK
| | - David A Menassa
- Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, Oxfordshire, UK.,Biological Sciences, Faculty of Environmental and Life Sciences, University of Southampton, Southampton, UK
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4
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Gröger N, Matas E, Gos T, Lesse A, Poeggel G, Braun K, Bock J. The transgenerational transmission of childhood adversity: behavioral, cellular, and epigenetic correlates. J Neural Transm (Vienna) 2016; 123:1037-52. [DOI: 10.1007/s00702-016-1570-1] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2015] [Accepted: 05/02/2016] [Indexed: 12/21/2022]
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5
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Exposure to a mildly aversive early life experience leads to prefrontal cortex deficits in the rat. Brain Struct Funct 2015; 221:4141-4157. [DOI: 10.1007/s00429-015-1154-0] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2015] [Accepted: 11/19/2015] [Indexed: 10/22/2022]
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6
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Soztutar E, Colak E, Ulupinar E. Gender- and anxiety level-dependent effects of perinatal stress exposure on medial prefrontal cortex. Exp Neurol 2015; 275 Pt 2:274-84. [PMID: 26057948 DOI: 10.1016/j.expneurol.2015.06.005] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2015] [Revised: 05/29/2015] [Accepted: 06/03/2015] [Indexed: 01/15/2023]
Abstract
Early life stress leads to psychopathological processes correlated with the predisposition of individuals. Prolonged development of the prefrontal cortex (PFC), playing a critical role in the cognition, personality and social behavior, makes it susceptible to adverse conditions. In this study, we evaluated the dendritic morphology of medial PFC neurons in rats subjected to perinatal stress exposure. Unbiased stereological counting methods showed that total number estimation of c-Fos (+) nuclei, indicating the neuronal activation upon stressful challenge, significantly increased in high anxious animals compared with low anxious and control groups, in both gender. Golgi-Cox staining of neurons displayed anxiety level- and sex-dependent reduction in the dendritic complexity and spine density of pyramidal neurons, especially in the stressed males. While the total length of dendrites were not correlational; density of spines, specifically the mushroom subtypes, showed a negative correlation with the anxiety level of stressed animals. These results suggest that medial PFC is a critical site of neural plasticity within the stressor controllability paradigm. Outcomes of early life stress might be predicted by analyzing the density and morphology of spines in the apical dendrites of pyramidal neurons in correlation with the anxiety-like behavior of animals.
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Affiliation(s)
- Erdem Soztutar
- Department of Anatomy, Faculty of Medicine, Eskisehir Osmangazi University, 26040, Eskisehir, Turkey; Interdisciplinary Neuroscience Department, Health Science Institute of Eskisehir Osmangazi University, 26040, Eskisehir, Turkey.
| | - Ertugrul Colak
- Department of Biostatistics and Medical Informatics, Faculty of Medicine, Eskisehir Osmangazi University, 26040, Eskisehir, Turkey.
| | - Emel Ulupinar
- Department of Anatomy, Faculty of Medicine, Eskisehir Osmangazi University, 26040, Eskisehir, Turkey; Interdisciplinary Neuroscience Department, Health Science Institute of Eskisehir Osmangazi University, 26040, Eskisehir, Turkey.
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7
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Powell SB, Khan A, Young JW, Scott CN, Buell MR, Caldwell S, Tsan E, de Jong LAW, Acheson DT, Lucero J, Geyer MA, Behrens MM. Early Adolescent Emergence of Reversal Learning Impairments in Isolation-Reared Rats. Dev Neurosci 2015; 37:253-62. [PMID: 26022788 DOI: 10.1159/000430091] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2014] [Accepted: 04/10/2015] [Indexed: 12/30/2022] Open
Abstract
Cognitive impairments appear early in the progression of schizophrenia, often preceding the symptoms of psychosis. Thus, the systems subserving these functions may be more vulnerable to, and mechanistically linked with, the initial pathology. Understanding the trajectory of behavioral and anatomical abnormalities relevant to the schizophrenia prodrome and their sensitivity to interventions in relevant models will be critical to identifying early therapeutic strategies. Isolation rearing of rats is an environmental perturbation that deprives rodents of social contact from weaning through adulthood and produces behavioral and neuronal abnormalities that mirror some pathophysiology associated with schizophrenia, e.g. frontal cortex abnormalities and prepulse inhibition (PPI) of startle deficits. Previously, we showed that PPI deficits in isolation-reared rats emerge in mid-adolescence (4 weeks after weaning; approx. postnatal day 52) but are not present when tested at 2 weeks after weaning (approx. postnatal day 38). Because cognitive deficits are reported during early adolescence, are relevant to the prodrome, and are linked to functional outcome, we examined the putative time course of reversal learning deficits in isolation-reared rats. Separate groups of male Sprague Dawley rats were tested in a two-choice discrimination task at 2 and 8 weeks after weaning, on postnatal day 38 and 80, respectively. The isolation-reared rats displayed impaired reversal learning at both time points. Isolation rearing was also associated with deficits in PPI at 4 and 10 weeks after weaning. The reversal learning deficits in the isolated rats were accompanied by reductions in parvalbumin immunoreactivity, a marker for specific subpopulations of GABAergic neurons, in the hippocampus. Hence, isolation rearing of rats may offer a unique model to examine the ontogeny of behavioral and neurobiological alterations that may be relevant to preclinical models of prodromal psychosis. © 2015 S. Karger AG, Basel.
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Affiliation(s)
- Susan B Powell
- Department of Psychiatry, School of Medicine, University of California San Diego, San Diego, Calif., USA
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8
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Transgenerational sex-specific impact of preconception stress on the development of dendritic spines and dendritic length in the medial prefrontal cortex. Brain Struct Funct 2014; 221:855-63. [PMID: 25395153 DOI: 10.1007/s00429-014-0940-4] [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] [Received: 07/24/2014] [Accepted: 11/01/2014] [Indexed: 10/24/2022]
Abstract
Perinatal adverse experience programs social and emotional behavioral traits and is a major risk factor for the development of behavioral and psychiatric disorders. Little information is available on how adversity to the mother prior to her first pregnancy (preconception stress, PCS) may affect brain structural development, which may underlie behavioral dysfunction in the offspring. Moreover, little is known about possible sex-dependent consequences of PCS in the offspring. This study examined spine number/density and dendritic length/complexity of layer II/III pyramidal neurons in the anterior cingulate (ACd), prelimbic/infralimbic (PL/IL) and orbitofrontal cortex (OFC) of male and female rats born to mothers exposed to unpredictable variable stress at different time points prior to reproduction. Our main findings are that in line with our hypothesis adversity to the mother before her pregnancy results in highly complex changes in neuronal morphology in the medial prefrontal, but not in the orbitofrontal cortical regions of her future offspring that persist into adulthood. Moreover, our study revealed that (1) in the PCS2 group (offspring of dams mated two weeks after stress) spine numbers and dendritic length and complexity were increased in response to PCS in the ACd and PL/IL, (2) these regional effects depended on the temporal proximity of adversity and conception, (3) in the ACd of the PCS2 group only males and the left hemispheres were affected. We speculate that these transgenerational brain structural changes are mediated by stress-induced epigenetic (re)programming of future gene activity in the oocyte.
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9
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Bock J, Rether K, Gröger N, Xie L, Braun K. Perinatal programming of emotional brain circuits: an integrative view from systems to molecules. Front Neurosci 2014; 8:11. [PMID: 24550772 PMCID: PMC3913903 DOI: 10.3389/fnins.2014.00011] [Citation(s) in RCA: 98] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2013] [Accepted: 01/17/2014] [Indexed: 02/06/2023] Open
Abstract
Environmental influences such as perinatal stress have been shown to program the developing organism to adapt brain and behavioral functions to cope with daily life challenges. Evidence is now accumulating that the specific and individual effects of early life adversity on the functional development of brain and behavior emerge as a function of the type, intensity, timing and the duration of the adverse environment, and that early life stress (ELS) is a major risk factor for developing behavioral dysfunctions and mental disorders. Results from clinical as well as experimental studies in animal models support the hypothesis that ELS can induce functional “scars” in prefrontal and limbic brain areas, regions that are essential for emotional control, learning and memory functions. On the other hand, the concept of “stress inoculation” is emerging from more recent research, which revealed positive functional adaptations in response to ELS resulting in resilience against stress and other adversities later in life. Moreover, recent studies indicate that early life experiences and the resulting behavioral consequences can be transmitted to the next generation, leading to a transgenerational cycle of adverse or positive adaptations of brain function and behavior. In this review we propose a unifying view of stress vulnerability and resilience by connecting genetic predisposition and programming sensitivity to the context of experience-expectancy and transgenerational epigenetic traits. The adaptive maturation of stress responsive neural and endocrine systems requires environmental challenges to optimize their functions. Repeated environmental challenges can be viewed within the framework of the match/mismatch hypothesis, the outcome, psychopathology or resilience, depends on the respective predisposition and on the context later in life.
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Affiliation(s)
- Jörg Bock
- PG "Epigenetics and Structural Plasticity", Institute of Biology, Otto von Guericke University Magdeburg Magdeburg, Germany ; Center for Behavioral Brain Sciences Magdeburg, Germany
| | - Kathy Rether
- PG "Epigenetics and Structural Plasticity", Institute of Biology, Otto von Guericke University Magdeburg Magdeburg, Germany ; Department of Zoology/Developmental Neurobiology, Institute of Biology, Otto von Guericke University Magdeburg Magdeburg, Germany
| | - Nicole Gröger
- Department of Zoology/Developmental Neurobiology, Institute of Biology, Otto von Guericke University Magdeburg Magdeburg, Germany
| | - Lan Xie
- PG "Epigenetics and Structural Plasticity", Institute of Biology, Otto von Guericke University Magdeburg Magdeburg, Germany ; Department of Zoology/Developmental Neurobiology, Institute of Biology, Otto von Guericke University Magdeburg Magdeburg, Germany
| | - Katharina Braun
- Center for Behavioral Brain Sciences Magdeburg, Germany ; Department of Zoology/Developmental Neurobiology, Institute of Biology, Otto von Guericke University Magdeburg Magdeburg, Germany
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10
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Himmler BT, Pellis SM, Kolb B. Juvenile play experience primes neurons in the medial prefrontal cortex to be more responsive to later experiences. Neurosci Lett 2013; 556:42-5. [PMID: 24103373 DOI: 10.1016/j.neulet.2013.09.061] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2013] [Revised: 09/24/2013] [Accepted: 09/26/2013] [Indexed: 01/17/2023]
Abstract
Juvenile play behavior in rats promotes later behavioral flexibility and appears to do so by modifying the neural systems that regulate the animal's response to unexpected challenges. For example, the experience of play has been shown to prune the dendritic arbor of the cells in the medial prefrontal cortex (mPFC), part of the brain's executive control system. The objective of the present study was to determine if the play-induced changes in the mPFC promotes greater plasticity to experiences later in life. In order to test this possibility, exposure to nicotine was used as the secondary experience given later in life, as it has been shown to produce later changes to the morphology of mPFC pyramidal neurons. Animals were either paired with three same-sex peers (play condition) or one adult (no play condition) during their juvenile period. As young adults, half of the rats from each condition were exposed to repeated injections of nicotine and the other half to injections of saline. The neural plasticity of the mPFC was measured by changes in length and branching of dendrites. Neural changes induced separately by play and by nicotine were consistent with previously published findings. The novel finding was that the cells in the mPFC exhibit a greater response to exposure to nicotine if the rats first had play experience. These findings suggest that juvenile play experiences enhance the plasticity of some neural systems.
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Affiliation(s)
- B T Himmler
- Department of Neuroscience, University of Lethbridge, Lethbridge, Alberta, Canada.
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11
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Hagenauer MH, Lee TM. Adolescent sleep patterns in humans and laboratory animals. Horm Behav 2013; 64:270-9. [PMID: 23998671 PMCID: PMC4780325 DOI: 10.1016/j.yhbeh.2013.01.013] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/04/2012] [Revised: 12/14/2012] [Accepted: 01/28/2013] [Indexed: 02/05/2023]
Abstract
This article is part of a Special Issue "Puberty and Adolescence". One of the defining characteristics of adolescence in humans is a large shift in the timing and structure of sleep. Some of these changes are easily observable at the behavioral level, such as a shift in sleep patterns from a relatively morning to a relatively evening chronotype. However, there are equally large changes in the underlying architecture of sleep, including a >60% decrease in slow brain wave activity, which may reflect cortical pruning. In this review we examine the developmental forces driving adolescent sleep patterns using a cross-species comparison. We find that behavioral and physiological sleep parameters change during adolescence in non-human mammalian species, ranging from primates to rodents, in a manner that is often hormone-dependent. However, the overt appearance of these changes is species-specific, with polyphasic sleepers, such as rodents, showing a phase-advance in sleep timing and consolidation of daily sleep/wake rhythms. Using the classic two-process model of sleep regulation, we demonstrate via a series of simulations that many of the species-specific characteristics of adolescent sleep patterns can be explained by a universal decrease in the build-up and dissipation of sleep pressure. Moreover, and counterintuitively, we find that these changes do not necessitate a large decrease in overall sleep need, fitting the adolescent sleep literature. We compare these results to our previous review detailing evidence for adolescent changes in the regulation of sleep by the circadian timekeeping system (Hagenauer and Lee, 2012), and suggest that both processes may be responsible for adolescent sleep patterns.
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Ventura R, Coccurello R, Andolina D, Latagliata EC, Zanettini C, Lampis V, Battaglia M, D'Amato FR, Moles A. Postnatal aversive experience impairs sensitivity to natural rewards and increases susceptibility to negative events in adult life. ACTA ACUST UNITED AC 2012; 23:1606-17. [PMID: 22669969 DOI: 10.1093/cercor/bhs145] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
Evidence shows that maternal care and postnatal traumatic events can exert powerful effects on brain circuitry development but little is known about the impact of early postnatal experiences on processing of rewarding and aversive stimuli related to the medial prefrontal cortex (mpFC) function in adult life. In this study, the unstable maternal environment induced by repeated cross-fostering (RCF) impaired palatable food conditioned place preference and disrupted the natural preference for sweetened fluids in the saccharin preference test. By contrast, RCF increased sensitivity to conditioned place aversion (CPA) and enhanced immobility in the forced swimming test. Intracerebral microdialysis data showed that the RCF prevents mpFC dopamine (DA) outflow regardless of exposure to rewarding or aversive stimuli, whereas it induces a strong and sustained prefrontal norepinephrine (NE) release in response to different aversive experiences. Moreover, the selective mpFC NE depletion abolished CPA, thus indicating that prefrontal NE is required for motivational salience attribution to aversion-related stimuli. These findings demonstrate that an unstable maternal environment impairs the natural propensity to seek pleasurable sources of reward, enhances sensitivity to negative events in adult life, blunts prefrontal DA outflow, and modulates NE release in the reverse manner depending on the exposure to rewarding or aversive stimuli.
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Affiliation(s)
- Rossella Ventura
- Santa Lucia Foundation, European Centre for Brain Research (CERC), Roma, Italy.
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13
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Muhammad A, Carroll C, Kolb B. Stress during development alters dendritic morphology in the nucleus accumbens and prefrontal cortex. Neuroscience 2012; 216:103-9. [PMID: 22542675 DOI: 10.1016/j.neuroscience.2012.04.041] [Citation(s) in RCA: 112] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2011] [Revised: 03/30/2012] [Accepted: 04/17/2012] [Indexed: 10/28/2022]
Abstract
The long-term effects of stress during development have been well characterized. However, the effects of developmental stress on the underlying neurological mechanisms related to the reward system are not well understood. The present report studied the long term effects of stress during development on the structural plasticity in the cortical and subcortical regions. Rats exposed to stress during embryonic development (prenatal stress; PS) or soon after birth (maternal separation; MS) were studied for structural alteration at the neuronal level in the nucleus accumbens (NAc), orbital frontal cortex (OFC), and medial prefrontal cortex (mPFC). The findings show that stress during development increased dendritic branching, length, and spine density in the NAc, and subregions of the PFC. PS experience increased dendritic branching and length in the mPFC apical and basilar dendrites. In contrast, a PS-associated decrease in dendritic branching and length was observed in the basilar branches of the OFC. MS resulted in an increase in dendritic growth and spine density in the subregions of the PFC. The effect of PS on neuroanatomy was more robust than MS despite the shorter duration and intensity. The altered dendritic growth and spine density associated with stress during development could have potential impact on NAc and PFC related behaviors.
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14
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Arg kinase regulates prefrontal dendritic spine refinement and cocaine-induced plasticity. J Neurosci 2012; 32:2314-23. [PMID: 22396406 DOI: 10.1523/jneurosci.2730-11.2012] [Citation(s) in RCA: 77] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Adolescence is characterized by vulnerability to the development of neuropsychiatric disorders including drug addiction, as well as prefrontal cortical refinement that culminates in structural stability in adulthood. Neuronal refinement and stabilization are hypothesized to confer resilience to poor decision making and addictive-like behaviors, although intracellular mechanisms are largely unknown. We characterized layer V prefrontal dendritic spine development and refinement in adolescent wild-type mice and mice lacking the cytoskeletal regulatory protein Abl-related gene (Arg) kinase. Relative to hippocampal CA1 pyramidal neurons, which exhibited a nearly linear increase in spine density up to postnatal day 60 (P60), wild-type prefrontal spine density peaked at P31, and then declined by 18% by P56-P60. In contrast, dendritic spines in mice lacking Arg destabilized by P31, leading to a net loss in both structures. Destabilization corresponded temporally to the emergence of exaggerated psychomotor sensitivity to cocaine. Moreover, cocaine reduced dendritic spine density in wild-type orbitofrontal cortex and enlarged remaining spine heads, but arg(-/-) spines were unresponsive. Local application of Arg or actin polymerization inhibitors exaggerated cocaine sensitization, as did reduced gene dosage of the Arg substrate, p190RhoGAP. Genetic and pharmacological Arg inhibition also retarded instrumental reversal learning and potentiated responding for reward-related cues, providing evidence that Arg regulates both psychomotor sensitization and decision-making processes implicated in addiction. These findings also indicate that structural refinement in the adolescent orbitofrontal cortex mitigates psychostimulant sensitivity and support the emerging perspective that the structural response to cocaine may, at any age, have behaviorally protective consequences.
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15
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Waddell J, McCarthy MM. Sexual differentiation of the brain and ADHD: what is a sex difference in prevalence telling us? Curr Top Behav Neurosci 2012; 9:341-60. [PMID: 21120649 PMCID: PMC4841632 DOI: 10.1007/7854_2010_114] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Sexual differentiation of the brain is a function of various processes that prepare the organism for successful reproduction in adulthood. Release of gonadal steroids during both the perinatal and the pubertal stages of development organizes many sex differences, producing changes in brain excitability and morphology that endure across the lifespan. To achieve these sexual dimorphisms, gonadal steroids capitalize on a number of distinct mechanisms across brain regions. Comparison of the developing male and female brain provides insight into the mechanisms through which synaptic connections are made, and circuits are organized that mediate sexually dimorphic behaviors. The prevalence of most psychiatric and neurological disorders differ in males versus females, including disorders of attention, activity and impulse control. While there is a strong male bias in incidence of attention deficit and hyperactivity disorders, the source of that bias remains controversial. By elucidating the biological underpinnings of male versus female brain development, we gain a greater understanding of how hormones and genes do and do not contribute to the differential vulnerability in one sex versus the other.
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Affiliation(s)
- Jaylyn Waddell
- Department of Physiology, School of Medicine, University of Maryland, Baltimore, MD, 21201, USA,
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Seidel K, Poeggel G, Holetschka R, Helmeke C, Braun K. Paternal deprivation affects the development of corticotrophin-releasing factor-expressing neurones in prefrontal cortex, amygdala and hippocampus of the biparental Octodon degus. J Neuroendocrinol 2011; 23:1166-76. [PMID: 21848809 DOI: 10.1111/j.1365-2826.2011.02208.x] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
Although the critical role of maternal care on the development of brain and behaviour of the offspring has been extensively studied, knowledge about the importance of paternal care is comparatively scarce. In biparental species, paternal care significantly contributes to a stimulating socio-emotional family environment, which most likely also includes protection from stressful events. In the biparental caviomorph rodent Octodon degus, we analysed the impact of paternal care on the development of neurones in prefrontal-limbic brain regions, which express corticotrophin-releasing factor (CRF). CRF is a polypeptidergic hormone that is expressed and released by a neuronal subpopulation in the brain, and which not only is essential for regulating stress and emotionality, but also is critically involved in cognitive functions. At weaning age [postnatal day (P)21], paternal deprivation resulted in an elevated density of CRF-containing neurones in the orbitofrontal cortex and in the basolateral amygdala of male degus, whereas a reduced density of CRF-expressing neurones was measured in the dentate gyrus and stratum pyramidale of the hippocampal CA1 region at this age. With the exception of the CA1 region, the deprivation-induced changes were no longer evident in adulthood (P90), which suggests a transient change that, in later life, might be normalised by other socio-emotional experience. The central amygdala, characterised by dense clusters of CRF-immunopositive neuropil, and the precentral medial, anterior cingulate, infralimbic and prelimbic cortices, were not affected by paternal deprivation. Taken together, this is the first evidence that paternal care interferes with the developmental expression pattern of CRF-expressing interneurones in an age- and region-specific manner.
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Affiliation(s)
- K Seidel
- Institute of Biology, Department of Zoology/Developmental Neurobiology, Otto-von-Guericke University, Magdeburg, Germany
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Eddison M, Guarnieri DJ, Cheng L, Liu CH, Moffat KG, Davis G, Heberlein U. arouser reveals a role for synapse number in the regulation of ethanol sensitivity. Neuron 2011; 70:979-90. [PMID: 21658589 DOI: 10.1016/j.neuron.2011.03.030] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/31/2011] [Indexed: 01/16/2023]
Abstract
A reduced sensitivity to the sedating effects of alcohol is a characteristic associated with alcohol use disorders (AUDs). A genetic screen for ethanol sedation mutants in Drosophila identified arouser (aru), which functions in developing neurons to reduce ethanol sensitivity. Genetic evidence suggests that aru regulates ethanol sensitivity through its activation by Egfr/Erk signaling and its inhibition by PI3K/Akt signaling. The aru mutant also has an increased number of synaptic terminals in the larva and adult fly. Both the increased ethanol sensitivity and synapse number of the aru mutant are restored upon adult social isolation, suggesting a causal relationship between synapse number and ethanol sensitivity. We thus show that a developmental abnormality affecting synapse number and ethanol sensitivity is not permanent and can be reversed by manipulating the environment of the adult fly.
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Affiliation(s)
- Mark Eddison
- Department of Anatomy, University of California San Francisco, San Francisco, CA 94158, USA.
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Prenatal stress and neonatal handling induce sex-specific changes in dendritic complexity and dendritic spine density in hippocampal subregions of prepubertal rats. Neuroscience 2011; 193:34-43. [PMID: 21807071 DOI: 10.1016/j.neuroscience.2011.07.048] [Citation(s) in RCA: 70] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2011] [Revised: 07/11/2011] [Accepted: 07/14/2011] [Indexed: 12/31/2022]
Abstract
Maternal stress during gestation in humans and experimental animals can result in emotional and cognitive dysfunction in the offspring. To facilitate our understanding of the underlying neuronal changes induced by prenatal stress (PNS), the dendritic and synaptic development was analyzed in three-dimensionally reconstructed Golgi-impregnated neurons in the hippocampal formation of offspring from pregnant dams which were stressed from day 15-20 by varied stressors. The analysis was focused on prepubertal rats and on the comparison of stress vulnerabilities in male and female offspring. In the hippocampal CA1 region PNS increased spine density on pyramidal neurons only in males, which thereby reached the levels observed in control females. On granular neurons of the dentate gyrus, PNS altered spine-density, dendritic length and dendritic complexity in opposite directions in males and females. In the CA3 area, PNS resulted in shorter and less complex dendrites in both sexes compared with unstressed controls. Another aim was to assess whether neonatal environmental interventions, such as handling (H) during the first 10 postnatal days, can reverse PNS-induced neuronal changes. We show here for the first time that H can "reverse" or prevent PNS-induced changes in spine density and dendritic length and complexity in a sex-, region- and dendrite-specific manner. These findings indicate that the sex-specific changes of neuronal and synaptic features in the hippocampal formation may represent a neuronal substrate of the stress-induced behavioral alterations and that these changes can be partly "normalized" by neonatal interventions.
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Bock J, Braun K. The impact of perinatal stress on the functional maturation of prefronto-cortical synaptic circuits: implications for the pathophysiology of ADHD? PROGRESS IN BRAIN RESEARCH 2011; 189:155-69. [PMID: 21489388 DOI: 10.1016/b978-0-444-53884-0.00023-3] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Enriched as well as impoverished or adverse perinatal environment plays an essential role in the development and refinement of neuronal pathways, which are the neural substrate of intellectual capacity and socioemotional competence. Perinatal experience and learning events continuously interact with the adaptive shaping of excitatory, inhibitory, and neuromodulatory synaptic as well as the endocrine stress systems, including the neuronal corticotropin-releasing factor (CRF) pathways. Adverse environments, such as stress and emotional deprivation can not only delay experience-dependent maturation of these pathways, but also induce permanent changes in prefronto-cortical wiring patterns. We assume that such dysfunctional connections are the neuronal basis for the development of psychosocially induced mental disorders during later life. The aim of this review is to focus on the impact of perinatal stress on the neuronal and synaptic reorganization during brain development and possible implications for the etiology and therapy of mental disorders such as ADHD.
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Affiliation(s)
- Jörg Bock
- Department of Zoology and Developmental Neurobiology, Institute of Biology, Otto von Guericke UniversityMagdeburg, Magdeburg, Germany
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Perry JL, Joseph JE, Jiang Y, Zimmerman RS, Kelly TH, Darna M, Huettl P, Dwoskin LP, Bardo MT. Prefrontal cortex and drug abuse vulnerability: translation to prevention and treatment interventions. ACTA ACUST UNITED AC 2010; 65:124-49. [PMID: 20837060 DOI: 10.1016/j.brainresrev.2010.09.001] [Citation(s) in RCA: 124] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2009] [Revised: 08/19/2010] [Accepted: 09/02/2010] [Indexed: 01/25/2023]
Abstract
Vulnerability to drug abuse is related to both reward seeking and impulsivity, two constructs thought to have a biological basis in the prefrontal cortex (PFC). This review addresses similarities and differences in neuroanatomy, neurochemistry and behavior associated with PFC function in rodents and humans. Emphasis is placed on monoamine and amino acid neurotransmitter systems located in anatomically distinct subregions: medial prefrontal cortex (mPFC); lateral prefrontal cortex (lPFC); anterior cingulate cortex (ACC); and orbitofrontal cortex (OFC). While there are complex interconnections and overlapping functions among these regions, each is thought to be involved in various functions related to health-related risk behaviors and drug abuse vulnerability. Among the various functions implicated, evidence suggests that mPFC is involved in reward processing, attention and drug reinstatement; lPFC is involved in decision-making, behavioral inhibition and attentional gating; ACC is involved in attention, emotional processing and self-monitoring; and OFC is involved in behavioral inhibition, signaling of expected outcomes and reward/punishment sensitivity. Individual differences (e.g., age and sex) influence functioning of these regions, which, in turn, impacts drug abuse vulnerability. Implications for the development of drug abuse prevention and treatment strategies aimed at engaging PFC inhibitory processes that may reduce risk-related behaviors are discussed, including the design of effective public service announcements, cognitive exercises, physical activity, direct current stimulation, feedback control training and pharmacotherapies. A major challenge in drug abuse prevention and treatment rests with improving intervention strategies aimed at strengthening PFC inhibitory systems among at-risk individuals.
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Affiliation(s)
- Jennifer L Perry
- Center for Drug Abuse Research Translation, University of Kentucky, Lexington, KY 40536-0509, USA
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Koe AS, Jones NC, Salzberg MR. Early life stress as an influence on limbic epilepsy: an hypothesis whose time has come? Front Behav Neurosci 2009; 3:24. [PMID: 19838325 PMCID: PMC2762371 DOI: 10.3389/neuro.08.024.2009] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2009] [Accepted: 08/18/2009] [Indexed: 01/14/2023] Open
Abstract
The pathogenesis of mesial temporal lobe epilepsy (MTLE), the most prevalent form of refractory focal epilepsy in adults, is thought to begin in early life, even though seizures may not commence until adolescence or adulthood. Amongst the range of early life factors implicated in MTLE causation (febrile seizures, traumatic brain injury, etc.), stress may be one important contributor. Early life stress is an a priori agent deserving study because of the large amount of neuroscientific data showing enduring effects on structure and function in hippocampus and amygdala, the key structures involved in MTLE. An emerging body of evidence directly tests hypotheses concerning early life stress and limbic epilepsy: early life stressors, such as maternal separation, have been shown to aggravate epileptogenesis in both status epilepticus and kindling models of limbic epilepsy. In addition to elucidating its influence on limbic epileptogenesis itself, the study of early life stress has the potential to shed light on the psychiatric disorder that accompanies MTLE. For many years, psychiatric comorbidity was viewed as an effect of epilepsy, mediated psychologically and/or neurobiologically. An alternative – or complementary – perspective is that of shared causation. Early life stress, implicated in the pathogenesis of several psychiatric disorders, may be one such causal factor. This paper aims to critically review the body of experimental evidence linking early life stress and epilepsy; to discuss the direct studies examining early life stress effects in current models of limbic seizures/epilepsy; and to suggest priorities for future research.
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Affiliation(s)
- Amelia S Koe
- Department of Medicine, Royal Melbourne Hospital, University of Melbourne Parkville, VIC, Australia
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Katz M, Liu C, Schaer M, Parker KJ, Ottet MC, Epps A, Buckmaster CL, Bammer R, Moseley ME, Schatzberg AF, Eliez S, Lyons DM. Prefrontal plasticity and stress inoculation-induced resilience. Dev Neurosci 2009; 31:293-9. [PMID: 19546566 DOI: 10.1159/000216540] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2009] [Accepted: 01/09/2009] [Indexed: 12/12/2022] Open
Abstract
Coping with mild early life stress tends to make subsequent coping efforts more effective and therefore more likely to be used as a means of arousal regulation and resilience. Here we show that this developmental learning-like process of stress inoculation increases ventromedial prefrontal cortical volumes in peripubertal monkeys. Larger volumes do not reflect increased cortical thickness but instead represent surface area expansion of ventromedial prefrontal cortex. Expansion of ventromedial prefrontal cortex coincides with increased white matter myelination inferred from diffusion tensor magnetic resonance imaging. These findings suggest that the process of coping with early life stress increases prefrontal myelination and expands a region of cortex that broadly controls arousal regulation and resilience.
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Affiliation(s)
- Maor Katz
- Department of Psychiatry, Stanford University, Stanford, Calif., USA
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Jones TA, Donlan NA, O'Donnell S. Growth and pruning of mushroom body Kenyon cell dendrites during worker behavioral development in the paper wasp, Polybia aequatorialis (Hymenoptera: Vespidae). Neurobiol Learn Mem 2009; 92:485-95. [PMID: 19539772 DOI: 10.1016/j.nlm.2009.06.007] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2008] [Revised: 06/03/2009] [Accepted: 06/11/2009] [Indexed: 12/01/2022]
Abstract
Adult workers of some social insect species show dramatic behavioral changes as they pass through a sequence of task specializations. In the paper wasp, Polybia aequatorialis, female workers begin adult life within the nest tending brood, progress to maintaining and defending the nest exterior, and ultimately leave the nest to forage. The mushroom body (MB) calyx neuropil increases in volume as workers progress from in-nest to foraging tasks. In other social Hymenoptera (bees and ants), MB Kenyon cell dendrites, axons and synapses change with the transition to foraging, but these neuronal effects had not been studied in wasps. Furthermore, the on-nest worker of Polybia wasps, an intermediate task specialization not identified in bees or ants, provides the opportunity to study pre-foraging worker class transitions. We asked whether Kenyon cell dendritic arborization varies with the task specialization of Polybia workers observed in the field near Monteverde, Costa Rica. Golgi-impregnated arbors in the lip and collar calyces, which receive a predominance of olfactory and visual input, respectively, were quantified using Sholl's concentric circles and a novel application of virtual spherical probes. Arbors of the lip varied in a manner reminiscent of honeybees, with foragers having the largest and in-nest workers having the smallest arbors. In contrast, arbors of the collar were largest in foragers but smallest in on-nest workers. Thus, progression through task specializations in P. aequatorialis involves subregion specific dendritic growth and regression in the MB neuropil. These results may reflect the sensitivity of Kenyon cell dendritic structure to specialization dependent social and sensory experience.
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Affiliation(s)
- Theresa A Jones
- Psychology Department and Institute for Neuroscience, University of Texas at Austin, Austin, TX 78746, USA.
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