Linked Life Data

9576886

Source:http://linkedlifedata.com/resource/pubmed/id/9576886

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
Pt 11
pubmed:dateCreated
1998-7-17
pubmed:abstractText
The mechanism of action of synthetic CCRF-DP, the corticotropin-releasing factor (CRF)-related diuretic peptide of the salt marsh mosquito Culex salinarius, was investigated in isolated Malpighian tubules of the yellow fever mosquito Aedes aegypti. A low concentration of CCRF-DP (10(-9)mol l-1) caused a small but insignificant increase in transepithelial secretion of NaCl and fluid, but significantly reduced transepithelial voltage and resistance without a change in short-circuit current, pointing to the stimulation of passive Cl- transport through the paracellular pathway as the principal mechanism of a mild diuresis. Significant changes in voltage and resistance but not in short-circuit current were duplicated by the ionophore A23187 (0.4 micromol l-1), suggesting Ca2+ as a second messenger at 10(-9)mol l-1 CCRF-DP. A high concentration of CCRF-DP (10(-7)mol l-1) significantly increased transepithelial secretion of NaCl and fluid and significantly increased short-circuit current, pointing to the stimulation of active Na+ transport through the transcellular pathway as the mechanism of a strong diuresis. This effect was mimicked by dibutyryl-cAMP, suggesting cAMP as a second messenger at 10(-7)mol l-1 CCRF-DP. Dibutyryl-cGMP had no effects. These results suggest dose-dependent, receptor-mediated effects of CCRF-DP that target discrete transport pathways via discrete second messengers: low concentrations of CCRF-DP cause a mild diuresis, apparently via Ca2+-mediated effects on paracellular Cl- transport, and high concentrations cause a strong diuresis via cAMP-mediated effects on active transcellular Na+ transport in addition to the effects on the paracellular pathway.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jun
pubmed:issn
0022-0949
pubmed:author
pubmed:issnType
Print
pubmed:volume
201
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1753-62
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1998
pubmed:articleTitle
The concentration-dependence of CRF-like diuretic peptide: mechanisms of action.
pubmed:affiliation
Department of Zoology, Washington State University, Pullman, WA 99164, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, Non-P.H.S.