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Predicate | Object |
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rdf:type | |
lifeskim:mentions | |
pubmed:issue |
6 Pt 2
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pubmed:dateCreated |
1997-8-18
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pubmed:abstractText |
Distal tubules (DT) from sham or five-sixths nephrectomized (Nx) rats were perfused in vivo to evaluate the hypothesis that, after Nx, endogenous angiotensin II (ANG II) modulates DT in vivo bicarbonate reabsorption (JtCO2) via H(+)-adenosinetriphosphatase (H(+)-ATPase) and Na+/H+ exchange. In Nx rats JtCO2 was increased (65 +/- 7 vs. -24 +/- 21 pmol.min-1.mm-1, P < 0.01). Both luminal and intravenous AT1-receptor blockade by losartan reduced Nx DT JtCO2 (41 +/- 6 and 34 +/- 4 pmol.min-1.min-1, respectively, P < 0.05), whereas neither 10(-9) M nor 10(-11) M ANG II luminal perfusion increased JtCO2, suggesting preexisting high endogenous ANG II levels. The Na+/H+ antiporter inhibitors 5-(N-ethyl-N-isopropyl)-amiloride and 5-(N,N-dimethyl)-amiloride were without effect. Luminal perfusion of 5 nM concanamycin A, a V-type H(+)-ATPase inhibitor, reduced Nx DT JtCO2 (45 +/- 8 pmol.min-1.mm-1, P < 0.05). In Nx A-type intercalated cells, we demonstrated cellular hypertrophy, elaboration of apical microplicae, and enhanced expression/apical polarization of H(+)-ATPase. Thus ANG II is an important determinant in sustaining brisk DT JtCO2 following Nx and is associated with enhanced expression and A-type intercalated cell apical polarization of H(+)-ATPase.
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pubmed:language |
eng
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pubmed:journal | |
pubmed:citationSubset |
IM
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pubmed:chemical | |
pubmed:status |
MEDLINE
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pubmed:month |
Jun
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pubmed:issn |
0002-9513
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pubmed:author | |
pubmed:issnType |
Print
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pubmed:volume |
272
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pubmed:owner |
NLM
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pubmed:authorsComplete |
Y
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pubmed:pagination |
F799-808
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pubmed:dateRevised |
2006-11-15
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pubmed:meshHeading |
pubmed-meshheading:9227642-Absorption,
pubmed-meshheading:9227642-Angiotensin II,
pubmed-meshheading:9227642-Animals,
pubmed-meshheading:9227642-Bicarbonates,
pubmed-meshheading:9227642-Blotting, Western,
pubmed-meshheading:9227642-Immunohistochemistry,
pubmed-meshheading:9227642-Kidney Tubules, Distal,
pubmed-meshheading:9227642-Male,
pubmed-meshheading:9227642-Microscopy, Electron,
pubmed-meshheading:9227642-Nephrectomy,
pubmed-meshheading:9227642-Proton-Translocating ATPases,
pubmed-meshheading:9227642-Rats,
pubmed-meshheading:9227642-Rats, Sprague-Dawley
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pubmed:year |
1997
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pubmed:articleTitle |
ANG II-dependent HCO3- reabsorption in surviving rat distal tubules: expression/activation of H(+)-ATPase.
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pubmed:affiliation |
Department of Medicine, University of Ottawa, Ontario, Canada.
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pubmed:publicationType |
Journal Article,
Research Support, Non-U.S. Gov't
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