Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
2002-5-23
pubmed:abstractText
Neuropeptide FF (NPFF) is a morphine modulatory peptide that plays an important role in a wide variety of physiological functions, including those related to nociception and central autonomic regulation. NPFF fibers and cells have been shown to be discretely localized in key autonomic centers within the brain, including the brainstem nucleus of the solitary tract (NTS). Central applications of NPFF evoke a number of important biological effects through activation of central neuronal circuits whose identities remain unknown at present. NPFF administered in this manner may also be capable of up- or down-regulating its own gene expression. In this study, we investigated the effects of intracerebroventricular (i.c.v.) administration of NPFF on the activation and the gene expression of NPFF in NTS neurons. Conscious rats received saline or NPFF (8 or 10 microg i.c.v.), with concomitant monitoring of arterial blood pressure. Brains were prepared for Fos immunohistochemistry to identify neuronal activation and NPFF in situ hybridization to determine cells expressing NPFF mRNA in the NTS. At a dose of 8 microg, i.c.v., NPFF did not evoke alterations in blood pressure, but, at 10 microg, there was an increase in arterial blood pressure of 30-40 mmHg. Image analysis showed a dose-dependent increase in number of NPFF neurons that were activated in rats receiving i.c.v. NPFF compared with saline controls. NPFF gene expression in the NTS showed a similar dose-dependent increase following i.c.v. administration of either 8 or 10 microg of NPFF. Significantly greater numbers of activated neurons expressing the NPFF gene (double labeled) were observed in the NTS at the level of the area postrema in animals receiving i.c.v. NPFF compared with saline controls. These data indicate that centrally administered NPFF is capable of up-regulating its own gene expression in the NTS and that this effect appears in part to be independent of elevations in arterial blood pressure that this peptide can evoke when administered i.c.v. at the higher dose. The up-regulation of NPFF may play a homeostatic role in response to specific cardiovascular challenges, such as hypotension.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jun
pubmed:issn
0021-9967
pubmed:author
pubmed:copyrightInfo
Copyright 2002 Wiley-Liss, Inc.
pubmed:issnType
Print
pubmed:day
3
pubmed:volume
447
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
300-7
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
2002
pubmed:articleTitle
Central administration of neuropeptide FF (NPFF) causes increased neuronal activation and up-regulation of NPFF gene expression in the rat brainstem.
pubmed:affiliation
Division of Neurology, Department of Medicine, University of Alberta, Edmonton, Alberta T6G 2S2, Canada. jack.jhamandas@ualberta.ca
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't