Linked Life Data

10564232

Source:http://linkedlifedata.com/resource/pubmed/id/10564232

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
5 Pt 2
pubmed:dateCreated
1999-12-20
pubmed:abstractText
Bradykinin (BK)-induced changes in intracellular calcium level ([Ca(2+)](i)) were studied on fura 2-loaded afferent (AA) and efferent glomerular arterioles (EA) microdissected from juxtamedullary renal cortex. A distinction was made between thin and muscular EA. In AA and both types of EA, BK increased [Ca(2+)](i) through activation of B(2) receptors located only on the endothelium. The responses were not affected by nifedipine (10(-6) M) and were smaller in a Ca(2+)-free medium, providing evidence that BK opens voltage-independent Ca(2+) channels and mobilizes intracellular Ca(2+). Thin EA differed from AA and muscular EA by a lower sensitivity to BK (EC(50) = 6.95 +/- 3.81 vs. 0.21 +/- 0.08 and 0.18 +/- 0.13 nM, respectively; P < 0.05), a higher maximal response (89 +/- 5 vs. 57 +/- 5 and 44 +/- 7 nM; P < 0.001), and a spontaneous return to basal Ca(2+) level, even in the presence of BK. Genistein (10(-4) M) and herbimycin A (25 x 10(-6) M), specific inhibitors of tyrosine kinases, inhibited the [Ca(2+)](i) responses exclusively in AA. Genistein reduced the peak and plateau phases of responses by 69 +/- 9 and 82 +/- 6%, respectively, in a medium with Ca(2+) and the peak by 48 +/- 9% in a Ca(2+)-free medium. Similar reductions were observed with herbimycin A. These results show that dissimilar signal transduction pathways are involved in BK effects on juxtamedullary arterioles and that a tyrosine kinase activity could participate in the regulation of BK effect on AA but not on EA.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Nov
pubmed:issn
0002-9513
pubmed:author
pubmed:issnType
Print
pubmed:volume
277
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
F697-705
pubmed:dateRevised
2009-11-19
pubmed:meshHeading
pubmed:year
1999
pubmed:articleTitle
Dissimilar mechanisms of Ca(2+) response to bradykinin in different types of juxtamedullary glomerular arterioles.
pubmed:affiliation
Physiology Laboratory, School of Medicine, 31062 Toulouse Cedex 4, France.
pubmed:publicationType
Journal Article, In Vitro, Research Support, Non-U.S. Gov't