Linked Life Data

3145280

Source:http://linkedlifedata.com/resource/pubmed/id/3145280

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
5
pubmed:dateCreated
1989-2-16
pubmed:abstractText
The rate of exchange of 18O between alveolar CO2 and lung water was measured in isolated perfused guinea pig lungs to quantify carbonic anhydrase (CA) activity. The average lung CA activity, with a reaction velocity constant of 5.32 +/- 2.2 s-1, is sufficient to accelerate CO2 reactions in lung water by two orders of magnitude over the uncatalyzed rate at 22 degrees C and a PCO2 of 40 Torr. Three sulfonamide inhibitors of CA with different human erythrocyte membrane permeabilities were used to determine the availability of the enzyme to the perfusate. Ethoxzolamide, the most permeable at 0.1 microM (100 times its inhibition constant, of Ki) inhibited 85% of enzyme activity after exposure of the lung for 3 min and 94% of enzyme activity after 30 min, whereas 1.25 microM (320 times its Ki) acetazolamide (1/165 as permeable) only inhibited CA 28% at 3 min and 75% at 30 min. Benzolamide (less than 1/1,000 as permeable) at 4 microM (1,000 times its Ki) inhibited only approximately 17% of control CA activity by 5 min and 48% by 30 min after the start of perfusion. These data indicate the CA available to pulmonary capillary plasma is approximately 10% of the total lung CA activity, in agreement with published measurements on the homogenized lung.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Nov
pubmed:issn
8750-7587
pubmed:author
pubmed:issnType
Print
pubmed:volume
65
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
2236-44
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1988
pubmed:articleTitle
Total CA activity in isolated perfused guinea pig lung by 18O-exchange method.
pubmed:affiliation
Department of Physiology, School of Medicine, University of Pennsylvania, Philadelphia 19104-6085.
pubmed:publicationType
Journal Article, In Vitro, Research Support, U.S. Gov't, P.H.S.