Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
2008-2-18
pubmed:abstractText
Epidemiological, clinical and experimental studies suggest that the cardioprotective effect of fish intake is mainly due to the antiarrhythmic properties of marine n-3 polyunsaturated fatty acids (PUFA), which modulate ion currents. Emerging evidences point to similar effects of alpha-linolenic acid (ALA), a vegetable n-3 PUFA, but much less is known about its effects on the specific cardiac ion channels. Using electrophysiology, protein biochemistry and fluorescence anisotropy measurements, we tested the effects of ALA on the atrial specific Kv1.5 channel. In stably transfected Ltk(-) cells, ALA blocked Kv1.5 channels in a time- and voltage-dependent manner with an IC(50) value of 3.7+/-0.3 microM. ALA at 2.5 microM inhibited the Kv1.5 current, shifted the midpoint of the activation curve by -8.8+/-4.3 mV (p<0.05), accelerated the activation kinetics of Kv1.5 due to a negative shift in its voltage dependency and slowed its deactivation process. Marine n-3 PUFA eicosapentaenoic and docosahexaenoic (EPA and DHA) acids, but not ALA, reduced the steady-state levels of Kv1.5 protein. DHA, but not ALA, increased the cell membrane order parameter. These results demonstrate that ALA directly blocks atria-specific Kv1.5 channels without modifying their expression or the bilayer order. Together, these effects suggest that the antiarrhythmic potential of diets enriched with plant-derived n-3 PUFA result, in part, from direct effects on cardiac ion channels.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Feb
pubmed:issn
1095-8584
pubmed:author
pubmed:issnType
Electronic
pubmed:volume
44
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
323-35
pubmed:meshHeading
pubmed:year
2008
pubmed:articleTitle
Modulation of the atrial specific Kv1.5 channel by the n-3 polyunsaturated fatty acid, alpha-linolenic acid.
pubmed:affiliation
Instituto de Farmacología y Toxicología CSIC/UCM, 28040 Madrid, Spain.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't, Research Support, N.I.H., Extramural