Switch to
Predicate | Object |
---|---|
rdf:type | |
lifeskim:mentions | |
pubmed:issue |
5 Pt 2
|
pubmed:dateCreated |
1985-12-13
|
pubmed:abstractText |
To examine the possible contribution of active H+ secretion mediated by brush border enzymes to proximal tubule HCO-3 absorption, paired reperfusions of surface proximal convoluted tubules were performed with the inhibitor dicyclohexylcarbodiimide (DCCD). In control studies using a solution devoid of HCO-3 but containing 5.5 mM glucose, 1 mM DCCD had no effect on glucose or fluid (Na+) absorption, suggesting that this inhibitor did not interfere with sodium entry at the brush border or mitochondrial energy production (ATP synthesis). In experiments using a perfusion solution containing 18-25 mM HCO-3, DCCD caused a fall in absolute CO2 absorption of approximately 15% under eucapneic conditions and 30% during acute hypercapnia. One millimole per liter amiloride (an inhibitor of the passive Na+-H+ exchanger) caused a 15% inhibition of CO2 absorption during acute hypercapnia and a disproportionately large reduction in fluid (Na+) absorption. The latter was not due to cell poisoning, since 1 mM amiloride had no inhibitory effect on fluid or glucose absorption when a HCO-3-free perfusion solution was used. Addition of 1 mM DCCD to a perfusion solution containing either 10(-3) M amiloride or 10(-4) M acetazolamide caused a significant inhibition of CO2 absorption compared with amiloride or acetazolamide alone. The observations are consistent with the view that in addition to passive Na+-H+ exchange, active transport mediated by either a H+-ATPase or a redox-driven H+ pump in the brush border contributes significantly to HCO-3 absorption in the proximal tubule.
|
pubmed:grant | |
pubmed:language |
eng
|
pubmed:journal | |
pubmed:citationSubset |
IM
|
pubmed:chemical |
http://linkedlifedata.com/resource/pubmed/chemical/Acetazolamide,
http://linkedlifedata.com/resource/pubmed/chemical/Amiloride,
http://linkedlifedata.com/resource/pubmed/chemical/Bicarbonates,
http://linkedlifedata.com/resource/pubmed/chemical/Carbodiimides,
http://linkedlifedata.com/resource/pubmed/chemical/Dicyclohexylcarbodiimide,
http://linkedlifedata.com/resource/pubmed/chemical/Drug Combinations,
http://linkedlifedata.com/resource/pubmed/chemical/Glucose
|
pubmed:status |
MEDLINE
|
pubmed:month |
Nov
|
pubmed:issn |
0002-9513
|
pubmed:author | |
pubmed:issnType |
Print
|
pubmed:volume |
249
|
pubmed:owner |
NLM
|
pubmed:authorsComplete |
Y
|
pubmed:pagination |
F636-44
|
pubmed:dateRevised |
2007-11-14
|
pubmed:meshHeading |
pubmed-meshheading:4061652-Absorption,
pubmed-meshheading:4061652-Acetazolamide,
pubmed-meshheading:4061652-Amiloride,
pubmed-meshheading:4061652-Animals,
pubmed-meshheading:4061652-Bicarbonates,
pubmed-meshheading:4061652-Carbodiimides,
pubmed-meshheading:4061652-Dicyclohexylcarbodiimide,
pubmed-meshheading:4061652-Drug Combinations,
pubmed-meshheading:4061652-Drug Resistance,
pubmed-meshheading:4061652-Glucose,
pubmed-meshheading:4061652-Hypercapnia,
pubmed-meshheading:4061652-Male,
pubmed-meshheading:4061652-Perfusion,
pubmed-meshheading:4061652-Rats,
pubmed-meshheading:4061652-Rats, Inbred Strains
|
pubmed:year |
1985
|
pubmed:articleTitle |
Evidence for a DCCD-sensitive component of proximal bicarbonate reabsorption.
|
pubmed:publicationType |
Journal Article,
Research Support, U.S. Gov't, P.H.S.
|