Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
4
pubmed:dateCreated
2006-8-21
pubmed:abstractText
In the proximal tubule, angiotensin II (Ang-II) regulates HCO(-)(3) reabsorption and H+ secretion by binding the type 1 Ang-II (AT1) receptor, stimulating Na(+)/HCO(-)(3) cotransport and Na(+)/H(+) exchange. Studies were carried out to determine if long-term changes in Ang-II receptor occupation alter the abundance of the basolateral Na(+)/HCO(-)(3) cotransporter (NBC1) or the apical membrane type 3 Na(+)/H(+) exchanger (NHE3). In the first set of experiments, rats eating a low-sodium diet were infused with the AT1 blocker, candesartan, or vehicle. In the second, lisinopril-infused rats were infused with either Ang II or vehicle. Transporter abundances were determined in whole kidney homogenates (WKH) and in brush border membrane (BBM) preparations by semiquantitative immunoblotting. Tissue distribution of transporters was assessed by immunocytochemistry. Blockade of the AT1 receptor by candesartan caused decreased abundance of NBC1 in WKH (59 +/- 9% of control; P<0.05) and Ang-II infusion increased abundance (130 +/- 7% of control; P<0.05). Changes in NBC1 in response to candesartan were confirmed immunohistochemically. Neither candesartan nor Ang II infusion affected the abundance of NHE3 in WKH or cortical homogenates. Candesartan decreased type 2 sodium-phosphate cotransporter abundance in both WKH (52 +/- 7% of control; P<0.05) and BBM (32 +/- 7% of control; P<0.05). Serum bicarbonate was decreased by candesartan and increased by Ang-II. Candesartan also decreased urinary ammonium excretion (P<0.05). The long-term effects of Ang-II in the proximal tubule may be mediated in part by regulation of NBC1 abundance, modifying bicarbonate reabsorption.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
http://linkedlifedata.com/resource/pubmed/chemical/Angiotensin II, http://linkedlifedata.com/resource/pubmed/chemical/Angiotensin II Type 1 Receptor..., http://linkedlifedata.com/resource/pubmed/chemical/Angiotensin Receptor Antagonists, http://linkedlifedata.com/resource/pubmed/chemical/Benzimidazoles, http://linkedlifedata.com/resource/pubmed/chemical/RNA, Messenger, http://linkedlifedata.com/resource/pubmed/chemical/Sodium-Bicarbonate Symporters, http://linkedlifedata.com/resource/pubmed/chemical/Sodium-Hydrogen Antiporter, http://linkedlifedata.com/resource/pubmed/chemical/Sodium-Phosphate Cotransporter..., http://linkedlifedata.com/resource/pubmed/chemical/Sodium-Potassium-Exchanging ATPase, http://linkedlifedata.com/resource/pubmed/chemical/Tetrazoles, http://linkedlifedata.com/resource/pubmed/chemical/candesartan
pubmed:status
MEDLINE
pubmed:month
Aug
pubmed:issn
0085-2538
pubmed:author
pubmed:issnType
Print
pubmed:volume
70
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
660-8
pubmed:dateRevised
2011-9-26
pubmed:meshHeading
pubmed-meshheading:16807546-Angiotensin II, pubmed-meshheading:16807546-Angiotensin II Type 1 Receptor Blockers, pubmed-meshheading:16807546-Angiotensin Receptor Antagonists, pubmed-meshheading:16807546-Animals, pubmed-meshheading:16807546-Benzimidazoles, pubmed-meshheading:16807546-Gene Expression Regulation, pubmed-meshheading:16807546-Gene Expression Regulation, Enzymologic, pubmed-meshheading:16807546-Kidney Tubules, Proximal, pubmed-meshheading:16807546-Male, pubmed-meshheading:16807546-RNA, Messenger, pubmed-meshheading:16807546-Rats, pubmed-meshheading:16807546-Rats, Inbred SHR, pubmed-meshheading:16807546-Sodium-Bicarbonate Symporters, pubmed-meshheading:16807546-Sodium-Hydrogen Antiporter, pubmed-meshheading:16807546-Sodium-Phosphate Cotransporter Proteins, Type II, pubmed-meshheading:16807546-Sodium-Potassium-Exchanging ATPase, pubmed-meshheading:16807546-Tetrazoles
pubmed:year
2006
pubmed:articleTitle
Long-term regulation of proximal tubule acid-base transporter abundance by angiotensin II.
pubmed:affiliation
Laboratory of Kidney and Electrolyte Metabolism, NHLBI, National Institutes of Health, Bethesda, Maryland 20892, USA.
pubmed:publicationType
Journal Article, Research Support, N.I.H., Extramural, Research Support, N.I.H., Intramural