Dendritic spines of the medial amygdala: plasticity, density, shape, and subcellular modulation by sex steroids

Autor(es)

Rasia-Filho, Alberto A. ^{[1, 2]} ; Dalpian, Francine ^[2] ; Menezes, Itiana C. ^[1] ; Brusco, Janaina ^{[3, 4]} ; Moreira, Jorge E. ^{[3, 4]} ; Cohen, Rochelle S. ^[5]

Afiliação do(s) autor(es)

^[1] Univ Fed Rio Grande do Sul, Grad Program Neurosci, BR-90046900 Porto Alegre, RS - Brazil

^[2] Fed Univ Hlth Sci Porto Alegre, Graduat Program Pathol, Dept Basic Sci Physiol, Porto Alegre, RS - Brazil

^[3] Univ Sao Paulo, Ribeirao Preto Sch Med, Dept Cell Mol Biol & Biopathogens, BR-05508 Sao Paulo - Brazil

^[4] Univ Sao Paulo, Ribeirao Preto Sch Med, Dept Neurosci & Behav, BR-05508 Sao Paulo - Brazil

^[5] Univ Illinois, Dept Anat & Cell Biol, Chicago, IL - USA

• Tipo de documento: Artigo de Revisão
• Fonte: HISTOLOGY AND HISTOPATHOLOGY; v. 27, n. 8, p. 985-1011, AUG 2012.
• Citações Web of Science: 26

Resumo

The medial nucleus of the amygdala (MeA) is a complex component of the ``extended amygdala{''} in rats. Its posterodorsal subnucleus (MePD) has a remarkable expression of gonadal hormone receptors, is sexually dimorphic or affected by sex steroids, and modulates various social behaviors. Dendritic spines show remarkable changes relevant for synaptic strength and plasticity. Adult males have more spines than females, the density of dendritic spines changes in the course of hours to a few days and is lower in proestrous and estrous phases of the ovarian cycle, or is affected by both sex steroid withdrawal and hormonal replacement therapy in the MePD. Males also have more thin spines than mushroom-like or stubby/wide ones. The presence of dendritic fillopodia and axonal protusions in the MePD neuropil of adult animals reinforces the evidence for local plasticity. Estrogen affects synaptic and cellular growth and neuroprotection in the MeA by regulating the activity of the cyclic AMP response element-binding protein (CREB)-related gene products, brain-derived neurotrophic factor (BDNF), the anti-apoptotic protein B-cell lymphoma-2 (Bcl-2) and the activity-regulated cytoskeleton-related protein (Arc). These effects on signal transduction cascades can also lead to local protein synthesis and/or rearrangement of the cytoskeleton and subsequent numerical/morphological alterations in dendritic spines. Various working hypotheses are raised from these experimental data and reveal the MePD as a relevant region to study the effects of sex steroids in the rat brain. (AU)

• Processo FAPESP: 03/03953-7 - Crio-preservação da ultraestrutura celular mantendo a qualidade antigênica: imunolocalização de proteínas desnaturáveis pela fixação química
• Beneficiário: Jorge Eduardo Moreira
• Linha de fomento: Auxílio à Pesquisa - Regular
• Processo FAPESP: 09/01571-6 - Amígdala medial de ratas ao longo do ciclo estral: morfologia, expressão de mRNAs, proteínas sinápticas e lateralidade
• Beneficiário: Jorge Eduardo Moreira
• Linha de fomento: Auxílio à Pesquisa - Regular
• Processo FAPESP: 11/10753-0 - Neurogênese e plasticidade sináptica no hipocampo de ratos submetidos à separação maternal e ao ambiente enriquecido
• Beneficiário: Jorge Eduardo Moreira
• Linha de fomento: Auxílio à Pesquisa - Regular