Linked Life Data

9474764

Source:http://linkedlifedata.com/resource/pubmed/id/9474764

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
1998-3-16
pubmed:abstractText
The transmembrane permeability coefficients of the environmentally sensitive arsenicals, monomethylarsonic acid (MMA) and dimethylarsinic acid (DMA) have been measured for egg phosphatidylcholine large unilamellar vesicles. The determination of the vesicle concentration-independent first-order rate constants for membrane transport and the permeability coefficients were made using an NMR technique employing shift agents. The permeability coefficient of DMA was found to be two orders of magnitude greater than that of MMA. This is attributed to the presence of MMAs extra hydroxyl group. Both species are shown to permeate membranes in the neutral form. Both the temperature dependence and the dependence on cholesterol content were investigated for DMA. The activation energy and the Arrhenius preexponential factor were found to be dependent on the cholesterol content. A marked increase in both parameters was observed up to 20 mol.% cholesterol, with a further, small increase up to 60%. The significance of these results to our understanding of membrane transport is discussed. The importance of using permeability coefficients rather than n-octanol/water partition coefficients in determining bioavailability and bioaccumulation of environmentally sensitive compounds is also discussed.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jan
pubmed:issn
0301-4622
pubmed:author
pubmed:issnType
Print
pubmed:day
1
pubmed:volume
70
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
75-85
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1998
pubmed:articleTitle
Vesicular membrane permeability of monomethylarsonic and dimethylarsinic acids.
pubmed:affiliation
University of British Columbia, Vancouver, Canada.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't