Switch to
Predicate | Object |
---|---|
rdf:type | |
lifeskim:mentions | |
pubmed:issue |
2 Pt 2
|
pubmed:dateCreated |
1997-9-25
|
pubmed:abstractText |
The major fraction of filtered Cl- is reabsorbed in the proximal tubule. An important component of Cl- reabsorption is passive and paracellular, driven by the lumen-negative potential difference in the early proximal tubule and the outwardly directed concentration gradient for Cl- in the later proximal tubule. Evidence suggests that a significant additional component of NaCl reabsorption in the proximal tubule is active and transcellular. Cl-/formate and Cl-/oxalate exchangers have been identified as mechanisms of uphill Cl- entry across the apical membrane. For steady-state Cl- absorption to occur by these mechanisms, formate and oxalate must recycle from lumen to cell. Recent studies indicate that recycling of formate occurs by H(+)-coupled formate transport in parallel with Na+/H+ exchange, whereas oxalate recycling takes place by oxalate/sulfate exchange in parallel with Na(+)-sulfate cotransport. The predominant route for Cl- exit across the basolateral membrane is via Cl- channels. Unresolved issues include the adequacy of formate recycling to sustain Cl- absorption by Cl-/formate exchange, the existence and contributions of additional mechanisms for apical Cl entry and basolateral Cl- exit, and the relative magnitudes of transcellular and paracellular transport under physiological conditions. In addition, the molecular identification and mechanisms of regulation of the Cl-/formate and Cl-/oxalate exchangers remain to be defined.
|
pubmed:grant | |
pubmed:language |
eng
|
pubmed:journal | |
pubmed:citationSubset |
IM
|
pubmed:chemical | |
pubmed:status |
MEDLINE
|
pubmed:month |
Aug
|
pubmed:issn |
0002-9513
|
pubmed:author | |
pubmed:issnType |
Print
|
pubmed:volume |
273
|
pubmed:owner |
NLM
|
pubmed:authorsComplete |
Y
|
pubmed:pagination |
F179-92
|
pubmed:dateRevised |
2007-11-14
|
pubmed:meshHeading |
pubmed-meshheading:9277578-Animals,
pubmed-meshheading:9277578-Anions,
pubmed-meshheading:9277578-Antiporters,
pubmed-meshheading:9277578-Biological Transport,
pubmed-meshheading:9277578-Biological Transport, Active,
pubmed-meshheading:9277578-Chloride-Bicarbonate Antiporters,
pubmed-meshheading:9277578-Chlorides,
pubmed-meshheading:9277578-Humans,
pubmed-meshheading:9277578-Kidney Tubules, Proximal,
pubmed-meshheading:9277578-Microvilli
|
pubmed:year |
1997
|
pubmed:articleTitle |
Mechanisms of chloride transport in the proximal tubule.
|
pubmed:affiliation |
Department of Internal Medicine, Yale University School of Medicine, New Haven, Connecticut 06520-8029, USA.
|
pubmed:publicationType |
Journal Article,
Research Support, U.S. Gov't, P.H.S.,
Review
|