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1.
Mol Psychiatry ; 23(4): 914-922, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-28439099

RESUMO

The lateral central nucleus of the amygdala (CeAL) and the dorsolateral bed nucleus of the stria terminalis (BNSTDL) coordinate the expression of shorter- and longer-lasting fears, respectively. Less is known about how these structures communicate with each other during fear acquisition. One pathway, from the CeAL to the BNSTDL, is thought to communicate via corticotropin-releasing factor (CRF), but studies have yet to examine its function in fear learning and memory. Thus, we developed an adeno-associated viral-based strategy to selectively target CRF neurons with the optogenetic silencer archaerhodopsin tp009 (CRF-ArchT) to examine the role of CeAL CRF neurons and projections to the BNSTDL during the acquisition of contextual fear. Expression of our CRF-ArchT vector injected into the amygdala was restricted to CeAL CRF neurons. Furthermore, CRF axonal projections from the CeAL clustered around BNSTDL CRF cells. Optogenetic silencing of CeAL CRF neurons during contextual fear acquisition disrupted retention test freezing 24 h later, but only at later time points (>6 min) during testing. Silencing CeAL CRF projections in the BNSTDL during contextual fear acquisition produced a similar effect. Baseline contextual freezing, the rate of fear acquisition, freezing in an alternate context after conditioning and responsivity to foot shock were unaffected by optogenetic silencing. Our results highlight how CeAL CRF neurons and projections to the BNSTDL consolidate longer-lasting components of a fear memory. Our findings have implications for understanding how discrete amygdalar CRF pathways modulate longer-lasting fear in anxiety- and trauma-related disorders.


Assuntos
Núcleo Central da Amígdala/metabolismo , Medo/fisiologia , Núcleos Septais/metabolismo , Tonsila do Cerebelo/metabolismo , Animais , Ansiedade/metabolismo , Condicionamento Clássico , Hormônio Liberador da Corticotropina/genética , Hormônio Liberador da Corticotropina/metabolismo , Masculino , Memória/fisiologia , Neurônios/metabolismo , Optogenética/métodos , Ratos , Ratos Endogâmicos SHR , Tálamo/metabolismo
2.
Dev Psychopathol ; 25(3): 577-585, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23527512

RESUMO

Early-life stress, such as maltreatment, institutionalization, and exposure to violence, is associated with accelerated telomere shortening. Telomere shortening may thus represent a biomarker of early adversity. Previous studies have suggested that responsive parenting may protect children from the negative biological and behavioral consequences of early adversity. This study examined the role of parental responsiveness in buffering children from telomere shortening following experiences of early-life stress. We found that high-risk children had significantly shorter telomeres than low-risk children, controlling for household income, birth weight, gender, and minority status. Further, parental responsiveness moderated the association between risk and telomere length, with more responsive parenting associated with longer telomeres only among high-risk children. These findings suggest that responsive parenting may have protective benefits on telomere shortening for young children exposed to early-life stress. Therefore, this study has important implications for early parenting interventions.


Assuntos
Acontecimentos que Mudam a Vida , Poder Familiar/psicologia , Pais/psicologia , Estresse Psicológico/genética , Encurtamento do Telômero , Adulto , Criança , Pré-Escolar , Feminino , Humanos , Estudos Longitudinais , Masculino , Estresse Psicológico/psicologia
3.
Behav Brain Res ; 302: 122-30, 2016 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-26778782

RESUMO

Contextual fear conditioning is a form of associative learning where animals must experience a context before they can associate it with an aversive stimulus. Single-trial contextual fear conditioning (sCFC) and the context preexposure facilitation effect (CPFE) are two variants of CFC where learning about the context is temporally contiguous (sCFC) with or separated (CPFE) from receiving a footshock in that context. Neural activity within CA1 of the dorsal hippocampus (CA1), amygdala (LA), and prefrontal cortex (PFC) may play a critical role when animals learn to associate a context with a footshock (i.e., training). Previous studies from our lab have found that early-growth-response gene 1 (Egr-1), an immediate early gene, exhibits unique patterns of activity within regions of the PFC following training in sCFC and the CPFE of juvenile rats. In the present study, we extended our studies by examining Egr-1 expression in young adult rats to determine (1) if our previous work reflected changes unique to development or extend into adulthood and (2) to contrast expression profiles between sCFC and the CPFE. Rats that learned context fear with sCFC showed increased Egr-1 in the anterior cingulate, orbitofrontal and infralimbic cortices relative to non-associative controls following training, but expression in prelimbic cortex did not differ between fear conditioned and non-associative controls. In contrast, rats trained in the CPFE also showed increased Egr-1 in all the prefrontal cortex regions, including prelimbic cortex. These findings replicate our previous findings in juveniles and suggest that Egr-1 in specific PFC subregions may be uniquely involved in learning context-fear in the CPFE compared to sCFC.


Assuntos
Proteínas de Transporte/metabolismo , Condicionamento Psicológico/fisiologia , Medo/psicologia , Regulação da Expressão Gênica no Desenvolvimento/fisiologia , Proteínas de Membrana/metabolismo , Córtex Pré-Frontal/metabolismo , Análise de Variância , Animais , Proteínas de Transporte/genética , Masculino , Proteínas de Membrana/genética , Ratos , Ratos Long-Evans , Retenção Psicológica , Fatores de Tempo
4.
Brain Res ; 1576: 63-72, 2014 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-24976583

RESUMO

We report activation of the immediate-early gene Egr-1 in the lateral amygdala (LA), hippocampus (CA1), and medial prefrontal cortex (mPFC) 30-min following the training phase in the context pre-exposure facilitation effect (CPFE) and standard context fear conditioning (180 s context exposure→shock). On day one of the CPFE paradigm, postnatal day (PD) 31 rats (±1) were pre-exposed to Context A (Pre) or Context B (Alt-Pre) for 5 min followed by five additional 1-min exposures. A day later, Pre and Alt-Pre rats received a 2-s, 1.5 mA footshock immediately upon placement in Context A. Animals included in in situ hybridization were then sacrificed 30 (±3) min later. On day three, the behaviorally-tested Pre rats showed significantly more fear-conditioned freezing in Context A than Alt-Pre rats. Standard context fear conditioning groups showed much greater freezing than the Pre group, as well as no shock and immediate-shock controls. Thirty minutes after immediate shock training, Pre rats showed increased Egr-1 mRNA in the prelimbic mPFC relative to Alt-Pre rats. Standard context conditioning selectively increased Egr-1 in CA1. In the LA and mPFC, Egr-1 increased to a similar extent in no shock, immediate shock, and standard context conditioning relative to homecage controls. The present study demonstrates that Egr-1 mRNA expression has a complex relationship to fear learning in different brain regions and variants of context conditioning.


Assuntos
Tonsila do Cerebelo/metabolismo , Condicionamento Clássico/fisiologia , Proteína 1 de Resposta de Crescimento Precoce/genética , Medo/fisiologia , Reação de Congelamento Cataléptica/fisiologia , Genes Precoces , Hipocampo/metabolismo , Proteínas do Tecido Nervoso/genética , Córtex Pré-Frontal/metabolismo , RNA Mensageiro/biossíntese , Fatores Etários , Tonsila do Cerebelo/fisiologia , Animais , Proteína 1 de Resposta de Crescimento Precoce/biossíntese , Proteína 1 de Resposta de Crescimento Precoce/fisiologia , Eletrochoque , Feminino , Manobra Psicológica , Hipocampo/fisiologia , Masculino , Proteínas do Tecido Nervoso/biossíntese , Proteínas do Tecido Nervoso/fisiologia , Plasticidade Neuronal , Córtex Pré-Frontal/fisiologia , RNA Mensageiro/genética , Ratos , Ratos Long-Evans , Fatores de Tempo
5.
Pak J Biol Sci ; 16(12): 580-4, 2013 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-24494528

RESUMO

This study was conducted to evaluate the plant growth promoting efficiency of combined inoculation of rhizobacteria on Vanilla plants. Based on the in vitro performance of indigenous Trichoderma spp. and Pseudomonas spp., four effective antagonists were selected and screened under greenhouse experiment for their growth enhancement potential. The maximum percentage of growth enhancement were observed in the combination of Trichoderma harzianum with Pseudomonas fluorescens treatment followed by Pseudomonas fluorescens, Trichoderma harzianum, Pseudomonas putida and Trichoderma virens, respectively in decreasing order. Combined inoculation of Trichoderma harzianum and Pseudomonas fluorescens registered the maximum length of vine (82.88 cm), highest number of leaves (26.67/plant), recorded the highest fresh weight of shoots (61.54 g plant(-1)), fresh weight of roots (4.46 g plant(-1)) and dry weight of shoot (4.56 g plant(-1)) where as the highest dry weight of roots (2.0806 g plant(-1)) were achieved with treatments of Pseudomonas fluorescens. Among the inoculated strains, combined inoculation of Trichoderma harzianum and Pseudomonas fluorescens recorded the maximum nitrogen uptake (61.28 mg plant(-1)) followed by the combined inoculation of Trichoderma harzianum (std) and Pseudomonas fluorescens (std) (55.03 mg plant(-1)) and the highest phosphorus uptake (38.80 mg plant(-1)) was recorded in dual inoculation of Trichoderma harzianum and Pseudomonas fluorescens.


Assuntos
Interações Hospedeiro-Patógeno , Pseudomonas fluorescens/crescimento & desenvolvimento , Trichoderma/crescimento & desenvolvimento , Vanilla/crescimento & desenvolvimento , Vanilla/microbiologia , Nitrogênio/metabolismo , Fósforo/metabolismo , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/microbiologia , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/microbiologia , Brotos de Planta/crescimento & desenvolvimento , Brotos de Planta/microbiologia , Fatores de Tempo , Trichoderma/classificação , Vanilla/metabolismo
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