Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
52
pubmed:dateCreated
2004-12-21
pubmed:abstractText
The vertebrate transient receptor potential cationic channel TRPV4 has been proposed as an osmo- and mechanosensor channel. Studies using knock-out animal models have further emphasized the relevance of the TRPV4 channel in the maintenance of the internal osmotic equilibrium and mechanosensation. However, at the cellular level, there is still one important question to answer: does the TRPV4 channel generate the Ca(2+) signal in those cells undergoing a Ca(2+)-dependent regulatory volume decrease (RVD) response? RVD in human airway epithelia requires the generation of a Ca(2+) signal to activate Ca(2+)-dependent K(+) channels. The RVD response is lost in airway epithelia affected with cystic fibrosis (CF), a disease caused by mutations in the cystic fibrosis transmembrane conductance regulator channel. We have previously shown that the defective RVD in CF epithelia is linked to the lack of swelling-dependent activation of Ca(2+)-dependent K(+) channels. In the present study, we show the expression of TRPV4 in normal human airway epithelia, where it functions as the Ca(2+) entry pathway that triggers the RVD response after hypotonic stress, as demonstrated by TRPV4 antisense experiments. However, cell swelling failed to trigger Ca(2+) entry via TRPV4 channels in CF airway epithelia, although the channel's response to a specific synthetic activator, 4 alpha-phorbol 12,13-didecanoate, was maintained. Furthermore, RVD was recovered in CF airway epithelia treated with 4 alpha-phorbol 12,13-didecanoate. Together, these results suggest that defective RVD in CF airway epithelia might be caused by the absence of a TRPV4-mediated Ca(2+) signal and the subsequent activation of Ca(2+)-dependent K(+) channels.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
http://linkedlifedata.com/resource/pubmed/chemical/CFTR protein, human, http://linkedlifedata.com/resource/pubmed/chemical/Calcium, http://linkedlifedata.com/resource/pubmed/chemical/Cation Transport Proteins, http://linkedlifedata.com/resource/pubmed/chemical/Cystic Fibrosis Transmembrane..., http://linkedlifedata.com/resource/pubmed/chemical/Ion Channels, http://linkedlifedata.com/resource/pubmed/chemical/Oligoribonucleotides, Antisense, http://linkedlifedata.com/resource/pubmed/chemical/Phorbol Esters, http://linkedlifedata.com/resource/pubmed/chemical/Potassium Channels..., http://linkedlifedata.com/resource/pubmed/chemical/TRPV Cation Channels, http://linkedlifedata.com/resource/pubmed/chemical/TRPV4 protein, human, http://linkedlifedata.com/resource/pubmed/chemical/phorbol-12,13-didecanoate
pubmed:status
MEDLINE
pubmed:month
Dec
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
24
pubmed:volume
279
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
54062-8
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed-meshheading:15489228-Calcium, pubmed-meshheading:15489228-Cation Transport Proteins, pubmed-meshheading:15489228-Cell Line, pubmed-meshheading:15489228-Cell Size, pubmed-meshheading:15489228-Cystic Fibrosis, pubmed-meshheading:15489228-Cystic Fibrosis Transmembrane Conductance Regulator, pubmed-meshheading:15489228-Epithelial Cells, pubmed-meshheading:15489228-Humans, pubmed-meshheading:15489228-Ion Channels, pubmed-meshheading:15489228-Mutation, pubmed-meshheading:15489228-Oligoribonucleotides, Antisense, pubmed-meshheading:15489228-Phorbol Esters, pubmed-meshheading:15489228-Potassium Channels, Calcium-Activated, pubmed-meshheading:15489228-Reverse Transcriptase Polymerase Chain Reaction, pubmed-meshheading:15489228-Signal Transduction, pubmed-meshheading:15489228-TRPV Cation Channels, pubmed-meshheading:15489228-Trachea, pubmed-meshheading:15489228-Transfection
pubmed:year
2004
pubmed:articleTitle
Swelling-activated Ca2+ entry via TRPV4 channel is defective in cystic fibrosis airway epithelia.
pubmed:affiliation
Laboratori de Fisiologia Molecular, Unitat de Senyalització Cellular, Universitat Pompeu Fabra, C/Dr. Aiguader 80, Barcelona 08003, Spain.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't