Linked Life Data

8331595

Source:http://linkedlifedata.com/resource/pubmed/id/8331595

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:dateCreated
1993-8-18
pubmed:abstractText
1. Neutral-carrier pH-sensitive microelectrodes were used to investigate intracellular pH (pHi) recovery from alkalinization in leech Retzius neurones in Hepes- and in CO2-HCO3(-)-buffered solution. The Retzius neurones were alkaline loaded by the addition and subsequent removal of 16 mM acetate, by changing from 5% CO2-27 mM HCO3- to 2% CO2-11 mM HCO3- or by changing from CO2-HCO3(-)- to Hepes-buffered solution. 2. In Hepes-buffered solution (pH 7.4) the mean pHi was 7.29 +/- 0.11 and the mean membrane potential -44.7 +/- 5.9 mV (mean +/- S.D.; n = 83). 3. The rate of pHi recovery from alkalinization increased with decreasing pH of the bathing medium (pHb). pHi changed about 0.30 pH units for a pHb unit change. 4. A decrease of extracellular buffer concentration (Hepes concentration lowered from 20 to 5 mM) caused an acidification of extracellular and intracellular pH and an acceleration of pHi recovery from alkalinization. 5. A depolarization of the Retzius cell membrane-induced by increasing the K+ concentration of the bathing medium from 4 to 20 mM (delta Em = 16.5 +/- 5.5 mV) or from 4 to 40 mM (delta Em = 24.8 +/- 3.5 mV)--evoked a decrease of pHi and an acceleration of pHi recovery from alkalinization. 6. The H+ current blocker Zn2+ (0.5 mM) inhibited pHi recovery from alkalinization at resting membrane potential as well as during depolarization. The inhibition was more pronounced during depolarization. 7. In Cl(-)-free, CO2-HCO3(-)-buffered solution pHi recovery from an alkaline load by changing from 5% CO2-27 mM HCO3- to 2% CO2-11 mM HCO3- was slowed by 48-71%. The rate of pHi recovery from an alkaline load induced by changing from CO2-HCO3- to Hepes buffer was reduced by 33-56% in Cl(-)-free solution. The removal of external Cl- did not affect pHi recovery in Hepes-buffered solution. 8. The pHi recovery from alkalinization was DIDS-insensitive in CO2-HCO3(-)- as in Hepes-buffered solutions and was not slowed in the absence of external Na+. 9. It is concluded that in Retzius neurones pHi recovery from alkalinization is mediated by a passive voltage-dependent H+ influx along the electrochemical proton gradient. In the presence of CO2-HCO3- buffer a DIDS-insensitive Cl(-)-HCO3- exchanger additionally regulates pHi after an intracellular alkaline load. It cannot be excluded that intracellular processes (e.g. H+ release from organelles, metabolic H+ production) are also involved in pHi recovery from alkalinization.
pubmed:commentsCorrections
http://linkedlifedata.com/resource/pubmed/commentcorrection/8331595-2157789, http://linkedlifedata.com/resource/pubmed/commentcorrection/8331595-2450997, http://linkedlifedata.com/resource/pubmed/commentcorrection/8331595-2462479, http://linkedlifedata.com/resource/pubmed/commentcorrection/8331595-2530172, http://linkedlifedata.com/resource/pubmed/commentcorrection/8331595-2538540, http://linkedlifedata.com/resource/pubmed/commentcorrection/8331595-2557442, http://linkedlifedata.com/resource/pubmed/commentcorrection/8331595-2821243, http://linkedlifedata.com/resource/pubmed/commentcorrection/8331595-2849529, http://linkedlifedata.com/resource/pubmed/commentcorrection/8331595-2849530, http://linkedlifedata.com/resource/pubmed/commentcorrection/8331595-2849531, http://linkedlifedata.com/resource/pubmed/commentcorrection/8331595-2985737, http://linkedlifedata.com/resource/pubmed/commentcorrection/8331595-3085512, http://linkedlifedata.com/resource/pubmed/commentcorrection/8331595-3202154, http://linkedlifedata.com/resource/pubmed/commentcorrection/8331595-3254411, http://linkedlifedata.com/resource/pubmed/commentcorrection/8331595-35433, http://linkedlifedata.com/resource/pubmed/commentcorrection/8331595-3559998, http://linkedlifedata.com/resource/pubmed/commentcorrection/8331595-38672, http://linkedlifedata.com/resource/pubmed/commentcorrection/8331595-4032303, http://linkedlifedata.com/resource/pubmed/commentcorrection/8331595-4838803, http://linkedlifedata.com/resource/pubmed/commentcorrection/8331595-6086903, http://linkedlifedata.com/resource/pubmed/commentcorrection/8331595-6086909, http://linkedlifedata.com/resource/pubmed/commentcorrection/8331595-6103001, http://linkedlifedata.com/resource/pubmed/commentcorrection/8331595-6324645, http://linkedlifedata.com/resource/pubmed/commentcorrection/8331595-6325586, http://linkedlifedata.com/resource/pubmed/commentcorrection/8331595-6434728, http://linkedlifedata.com/resource/pubmed/commentcorrection/8331595-6707968, http://linkedlifedata.com/resource/pubmed/commentcorrection/8331595-7012859, http://linkedlifedata.com/resource/pubmed/commentcorrection/8331595-7108786, http://linkedlifedata.com/resource/pubmed/commentcorrection/8331595-7133121, http://linkedlifedata.com/resource/pubmed/commentcorrection/8331595-7316213, http://linkedlifedata.com/resource/pubmed/commentcorrection/8331595-7420016, http://linkedlifedata.com/resource/pubmed/commentcorrection/8331595-7441547
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Mar
pubmed:issn
0022-3751
pubmed:author
pubmed:issnType
Print
pubmed:volume
462
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
627-43
pubmed:dateRevised
2009-11-18
pubmed:meshHeading
pubmed:year
1993
pubmed:articleTitle
pH recovery from intracellular alkalinization in Retzius neurones of the leech central nervous system.
pubmed:affiliation
Institut für Zoologie/Lehrstuhl für Neurobiologie, Heinrich-Heine-Universität, Düsseldorf, Germany.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't