Navegando por Palavras-chave "Edinger-Westphal nucleus"

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    CRF family peptides are differently altered by acute restraint stress and chronic unpredictable stress
    (Elsevier B.V., 2014-09-01) Andrade, José Simões de [UNIFESP]; Viana, Milena de Barros [UNIFESP]; Abrão, Renata Oliveira [UNIFESP]; Bittencourt, Jackson C.; Céspedes, Isabel Cristina [UNIFESP]; Universidade Federal de São Paulo (UNIFESP); Universidade de São Paulo (USP)
    Corticotropin-releasing factor (CRF) acts to promote stress-like physiological and behavioral responses and is mainly expressed in the paraventricular hypothalamic nucleus (PVN). Urocortin 1 (Ucn1) is also a ligand to CRF type 1 and 2 receptors that has been associated with the stress response. Ucnl neurons are primarily found in the Edinger-Westphal (EW) nucleus. It has been previously proposed that CRF and Ucnl differently modulate stress responses to distinct types of stressors. the present study used male Wistar rats to compare the effects of acute restraint stress and unpredictable chronic stress (UCS) through Fos-immunoreactivity (Fos-ir) on CRF-containing neurons of PVN and Ucn1-containing EW centrally projecting neurons. Results showed that PVN neurons responded to both acute restraint and UCS. Also for the PVN, unspecific variables, dependent on the time animals remained in the laboratory, do not seem to alter Fos-ir, since no significant differences between acute and chronic control groups were found. On the other hand, EW neurons were only activated in response to acute restraint stress. Also, for this nucleus a significant difference was found between acute and chronic control groups, suggesting that unspecific variables, dependent on the time animals remain in the laboratory, interfere with the nucleus activation. These results suggest that CRF/Ucn1 neuronal circuits encompass two interconnected systems, which are coordinated to respond to acute stressors, but are differentially activated during chronic unpredictable stress. (C) 2014 Elsevier B.V. All rights reserved.
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    mRNA expression of corticotropin-releasing factor and urocortin 1 after restraint and foot shock together with alprazolam administration
    (Elsevier B.V., 2010-12-01) Céspedes, Isabel Cristina [UNIFESP]; Oliveira, Amanda R. de; Silva, Joelcimar M. da; Silva, Andre V. da; Sita, Luciane V.; Bittencourt, Jackson C.; Universidade Federal de São Paulo (UNIFESP); Universidade de São Paulo (USP)
    Corticotropin-releasing factor (CRF) is expressed in the paraventricular nucleus of the hypothalamus (PVN), and act centrally to provoke stress-like autonomic and behavioral responses. Urocortins 1-3 are additional ligands to the CRF receptors 1 and 2. Ucn 1 neurons are primarily concentrated in the Edinger-Westphal (EW) nucleus and also have been associated with stress responses. It is also known that UCN 1 respond in different ways depending on the stressor presented. Benzodiazepines can act via the CRF peptidergic system and chronic administration of alprazolam does not interfere with CRF mRNA expression in the PVN, but significantly increase Ucn 1 mRNA expression in the EW. the aim of our study was to investigate the relationship between different stressor stimuli, foot shock (FS) and restraint (R), and the mRNA expression of CRF and Ucn 1 in the PVN and EW using alprazolam (A). We employed fos activation and in situ hybridization. Restraint group presented increased fos-ir and CRF mRNA expression in the PVN compared to FS group. the stress responses of R group were prevented by A. in the EW,fos-ir was higher in the FS group than in the R group, whereas Ucn 1 mRNA expression was higher in the R group than in the FS group. Alprazolam significantly increased fos-ir and Ucn 1 mRNA expression in both groups. Our results show that PVN and EW respond in different ways to the same stressors. Furthermore, EW of stressed animals replies in a complementary way comparing to PVN with the use of Alprazolam. (C) 2010 Elsevier Inc. All rights reserved.