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Predicate | Object |
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rdf:type | |
lifeskim:mentions | |
pubmed:issue |
4
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pubmed:dateCreated |
1995-2-22
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pubmed:abstractText |
In non-differentiated NG108-15 cells, both angiotensin II (Ang II) (100 nM) and CGP 42112 (100 nM) decreased the T-type calcium current amplitude by 24 +/- 2% and 21 +/- 3%, respectively. cGMP is not a mediator of the Ang II effect, since loading of cells with 50 microM cGMP did not prevent the inhibitory effects of Ang II. The effects of Ang II involves a non-identified GTPase activity since incubation with GDP beta S (3 mM) completely reversed the inhibitory effect of Ang II while GTP gamma S mimicked its effect. However, Ang II binding was not affected by GTP gamma S, and the effect of Ang II was not modified in pertussis toxin-treated cells. The inhibitory effect of Ang II on the T-type Ca2+ current involves a phosphotyrosine phosphatase activity since sodium orthovanadate prevented the effects of Ang II, although microcystin-LR, a selective Ser/Thr phosphatase 1 and 2A inhibitor, did not modify the effect of Ang II. These results provide the first evidence of a modulation of membrane conductance by Ang II through the AT2 receptor and demonstrate the involvement of a phosphotyrosine phosphatase and a G protein in the AT2 transduction mechanism in NG108-15 cells. Moreover, our data suggest that phosphotyrosine phosphatase activation is proximal to receptor occupation, since sodium orthovanadate inhibits both GTPase activity and T-type current blockage induced by Ang II or CGP 42112, while GTP gamma S inhibition of the T-type calcium current is not impaired.
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pubmed:language |
eng
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pubmed:journal | |
pubmed:citationSubset |
IM
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pubmed:chemical |
http://linkedlifedata.com/resource/pubmed/chemical/Angiotensin II,
http://linkedlifedata.com/resource/pubmed/chemical/CGP 42112A,
http://linkedlifedata.com/resource/pubmed/chemical/Calcium Channels,
http://linkedlifedata.com/resource/pubmed/chemical/Cyclic GMP,
http://linkedlifedata.com/resource/pubmed/chemical/GTP-Binding Proteins,
http://linkedlifedata.com/resource/pubmed/chemical/Oligopeptides,
http://linkedlifedata.com/resource/pubmed/chemical/Receptors, Angiotensin
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pubmed:status |
MEDLINE
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pubmed:month |
Jan
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pubmed:issn |
0021-9258
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pubmed:author | |
pubmed:issnType |
Print
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pubmed:day |
27
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pubmed:volume |
270
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pubmed:owner |
NLM
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pubmed:authorsComplete |
Y
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pubmed:pagination |
1670-4
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pubmed:dateRevised |
2006-11-15
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pubmed:meshHeading |
pubmed-meshheading:7829501-Angiotensin II,
pubmed-meshheading:7829501-Animals,
pubmed-meshheading:7829501-Calcium Channels,
pubmed-meshheading:7829501-Cyclic GMP,
pubmed-meshheading:7829501-GTP-Binding Proteins,
pubmed-meshheading:7829501-Glioma,
pubmed-meshheading:7829501-Hybrid Cells,
pubmed-meshheading:7829501-Kinetics,
pubmed-meshheading:7829501-Membrane Potentials,
pubmed-meshheading:7829501-Neuroblastoma,
pubmed-meshheading:7829501-Oligopeptides,
pubmed-meshheading:7829501-Patch-Clamp Techniques,
pubmed-meshheading:7829501-Receptors, Angiotensin,
pubmed-meshheading:7829501-Time Factors
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pubmed:year |
1995
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pubmed:articleTitle |
A G protein is involved in the angiotensin AT2 receptor inhibition of the T-type calcium current in non-differentiated NG108-15 cells.
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pubmed:affiliation |
Service of Endocrinology, Faculty of Medicine, University of Sherbrooke, Québec, Canada.
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pubmed:publicationType |
Journal Article,
Research Support, Non-U.S. Gov't
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