Linked Life Data

6748054

Source:http://linkedlifedata.com/resource/pubmed/id/6748054

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
1984-8-24
pubmed:abstractText
The effects of stepwise concentration changes of K+ and HCO3- in the basolateral solution on the basolateral membrane potential (Vbl) of proximal tubule cells of the doubly-perfused Necturus kidney were examined using conventional microelectrodes. Apparent transference numbers were calculated from changes in Vb1 after alterations in external K+ concentration from 1.0 to 2.5 mM (tK, 1.0-2.5), 2.5 to 10, and in external HCO3- concentration (at constant pH) from 5 to 10 mM (tHCO3, 5-10), 10 to 20, or 10 to 50. tK, 2.5-10 was 0.38 +/- 0.02 under control conditions but was sharply reduced to 0.08 +/- 0.03 (P greater than 0.001) by 4 mM Ba++. This concentration of Ba++ reduced Vb1 by 9 +/- 1 mV (at 2.5 external K+). Perfusion with SITS (5 X 10(-4)M) for 1 hr hyperpolarized Vb1 by 10 +/- 3 mV and increased tK, 2.5-10 significantly to 0.52 +/- 0.01 (P less than 0.001). Ba++ application in the presence of SITS depolarized Vb1 by 22 +/- 3 mV. In control conditions tHCO3, 10-50 was 0.63 +/- 0.05 and was increased to 0.89 +/- 0.07 (P less than 0.01) by Ba++ but was decreased to 0.14 +/- 0.02 (P less than 0.001) by SITS. In the absence of apical and basolateral chloride, the response of Vb1 to bicarbonate was diminished but still present (tHO3, 10-20 was 0.35 +/- 0.03). Intracellular pH, measured with liquid ion-exchange microelectrodes, increased from 7.42 +/- 0.19 to 7.57 +/- 0.17 (P less than 0.02) when basolateral bicarbonate was increased from 10 to 20 mM at constant pH. These data show that the effects of bicarbonate on Vb1 are largely independent of effects on the K+ conductance and that there is a significant current-carrying bicarbonate pathway in the basolateral membrane.(ABSTRACT TRUNCATED AT 250 WORDS)
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:issn
0022-2631
pubmed:author
pubmed:issnType
Print
pubmed:volume
79
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
145-52
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1984
pubmed:articleTitle
Electrical effects of potassium and bicarbonate on proximal tubule cells of Necturus.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't