Linked Life Data

17553493

Source:http://linkedlifedata.com/resource/pubmed/id/17553493

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
2007-7-30
pubmed:abstractText
The present study evaluated the involvement of glucocorticoid in the activation of vasopressinergic and oxytocinergic neurons of hypothalamic nuclei and plasma levels of vasopressin (AVP), oxytocin (OT), atrial natriuretic peptide (ANP) and corticosterone (CORT) in response to both isotonic and hypertonic blood volume expansion (BVE). Rats were subjected to isotonic (0.15 M NaCl, 2 ml/100 g b.w., i.v.) or hypertonic (0.30 M NaCl, 2 ml/100 g b.w., i.v.) BVE with or without pre-treatment with dexamethasone (1 mg/kg, i.p.). Results showed that isotonic BVE increased OT, ANP and CORT, and decreased AVP plasma levels. On the other hand, hypertonic BVE enhanced AVP, ANP, OT, and CORT plasma concentrations. Both hypertonic and isotonic BVE induced an increase in the number of Fos-OT double-labeled magnocellular neurons in the PVN and SON. Pre-treatment with dexamethasone reduced OT secretion, as well as Fos-OT immunoreactive neurons in response to both isotonic and hypertonic BVE. We also observed that dexamethasone pre-treatment had no effect on AVP secretion in response to hypertonic BVE, although this effect was associated with a blockade of Fos expression in the vasopressinergic magnocellular neurons in the PVN and SON. In conclusion, these data suggest that, not only the rapid OT release from storages, but also the oxytocinergic cellular activation induced by BVE are modulated by glucocorticoids. However, this pattern of response was not observed for AVP cells, suggesting that dexamethasone is not likely to influence rapid release of AVP but seems to modulate the activation of these neurons in response to hypertonic BVE.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Aug
pubmed:issn
0014-4886
pubmed:author
pubmed:issnType
Print
pubmed:volume
206
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
192-200
pubmed:meshHeading
pubmed-meshheading:17553493-Animals, pubmed-meshheading:17553493-Arginine Vasopressin, pubmed-meshheading:17553493-Atrial Natriuretic Factor, pubmed-meshheading:17553493-Blood Volume, pubmed-meshheading:17553493-Corticosterone, pubmed-meshheading:17553493-Dexamethasone, pubmed-meshheading:17553493-Glucocorticoids, pubmed-meshheading:17553493-Hypothalamo-Hypophyseal System, pubmed-meshheading:17553493-Hypotonic Solutions, pubmed-meshheading:17553493-Immunohistochemistry, pubmed-meshheading:17553493-Male, pubmed-meshheading:17553493-Neurons, pubmed-meshheading:17553493-Neuropeptides, pubmed-meshheading:17553493-Oxytocin, pubmed-meshheading:17553493-Pituitary-Adrenal System, pubmed-meshheading:17553493-Proto-Oncogene Proteins c-fos, pubmed-meshheading:17553493-Rats, pubmed-meshheading:17553493-Rats, Wistar, pubmed-meshheading:17553493-Saline Solution, Hypertonic, pubmed-meshheading:17553493-Water-Electrolyte Balance
pubmed:year
2007
pubmed:articleTitle
Glucocorticoid modulation of neuronal activity and hormone secretion induced by blood volume expansion.
pubmed:affiliation
Departamento de Fisiologia, Faculdade de Medicina de Ribeirao Preto, Universidade de São Paulo, Brazil.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't