Linked Life Data

17012249

Source:http://linkedlifedata.com/resource/pubmed/id/17012249

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
12
pubmed:dateCreated
2006-10-2
pubmed:abstractText
We report here the application of a previously described method to directly determine the CO2 permeability (P(CO2)) of the cell membranes of normal human red blood cells (RBCs) vs. those deficient in aquaporin 1 (AQP1), as well as AQP1-expressing Xenopus laevis oocytes. This method measures the exchange of (18)O between CO2, HCO3(-), and H2O in cell suspensions. In addition, we measure the alkaline surface pH (pH(S)) transients caused by the dominant effect of entry of CO2 vs. HCO3(-) into oocytes exposed to step increases in [CO2]. We report that 1) AQP1 constitutes the major pathway for molecular CO2 in human RBCs; lack of AQP1 reduces P(CO2) from the normal value of 0.15 +/- 0.08 (SD; n=85) cm/s by 60% to 0.06 cm/s. Expression of AQP1 in oocytes increases P(CO2) 2-fold and doubles the alkaline pH(S) gradient. 2) pCMBS, an inhibitor of the AQP1 water channel, reduces P(CO2) of RBCs solely by action on AQP1 as it has no effect in AQP1-deficient RBCs. 3) P(CO2) determinations of RBCs and pH(S) measurements of oocytes indicate that DIDS inhibits the CO2 pathway of AQP1 by half. 4) RBCs have at least one other DIDS-sensitive pathway for CO2. We conclude that AQP1 is responsible for 60% of the high P(CO2) of red cells and that another, so far unidentified, CO2 pathway is present in this membrane that may account for at least 30% of total P(CO2).
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Oct
pubmed:issn
1530-6860
pubmed:author
pubmed:issnType
Electronic
pubmed:volume
20
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1974-81
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
2006
pubmed:articleTitle
Evidence that aquaporin 1 is a major pathway for CO2 transport across the human erythrocyte membrane.
pubmed:affiliation
Zentrum Physiologie, Abt. Vegetative Physiologie, Medizinische Hochschule Hannover, 30625 Hannover, Germany.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't