Suppression of Calcium Sparks in Rat Ventricular Myocytes and Direct Inhibition of Sheep Cardiac RyR Channels by EPA, DHA and Oleic Acid

Suppression of Calcium Sparks in Rat Ventricular Myocytes and Direct Inhibition of Sheep Cardiac... The anti-arrhythmic effects of long-chain polyunsaturated fatty acids (PUFAs) may be related to their ability to alter calcium handling in cardiac myocytes. We investigated the effect of eicosapentanoic acid (EPA) and docosahexaenoic acid (DHA) on calcium sparks in rat cardiac myocytes and the effects of these PUFAs and the monounsaturated oleic acid on cardiac calcium release channels (RyRs). Visualization of subcellular calcium concentrations in single rat ventricular myocytes showed that intensity of calcium sparks was reduced in the presence of EPA and DHA (15 µM). It was also found that calcium sparks decayed more quickly in the presence of EPA but not DHA. Sarcoplasmic vesicles containing RyRs were prepared from sheep hearts and RyR activity was determined by either [3H]ryanodine binding or by single-channel recording. Bilayers were formed from phosphatidylethanolamine and phosphatidylcholine dissolved in either n-decane or n-tetradecane. EPA inhibited [3H]ryanodine binding to RyRs in SR vesicles with K I = 40 µM. Poly- and mono-unsaturated free fatty acids inhibited RyR activity in lipid bilayers. EPA (cytosolic or luminal) inhibited RyRs with K I =32 µM and Hill coefficient, n 1 = 3.8. Inhibition was independent of the n-alkane solvent and whether RyRs were activated by ATP or Ca2+. DHA and oleic acid also inhibited RyRs, suggesting that free fatty acids generally inhibit RyRs at micromolar concentrations. http://www.deepdyve.com/assets/images/DeepDyve-Logo-lg.png The Journal of Membrane Biology Springer Journals

Suppression of Calcium Sparks in Rat Ventricular Myocytes and Direct Inhibition of Sheep Cardiac RyR Channels by EPA, DHA and Oleic Acid

Loading next page...
 
/lp/springer_journal/suppression-of-calcium-sparks-in-rat-ventricular-myocytes-and-direct-J8U4Zy4myA
Publisher
Springer Journals
Copyright
Copyright © 2003 by Springer-Verlag New York Inc.
Subject
Philosophy
ISSN
0022-2631
eISSN
1432-1424
D.O.I.
10.1007/s00232-003-0628-9
Publisher site
See Article on Publisher Site

Abstract

The anti-arrhythmic effects of long-chain polyunsaturated fatty acids (PUFAs) may be related to their ability to alter calcium handling in cardiac myocytes. We investigated the effect of eicosapentanoic acid (EPA) and docosahexaenoic acid (DHA) on calcium sparks in rat cardiac myocytes and the effects of these PUFAs and the monounsaturated oleic acid on cardiac calcium release channels (RyRs). Visualization of subcellular calcium concentrations in single rat ventricular myocytes showed that intensity of calcium sparks was reduced in the presence of EPA and DHA (15 µM). It was also found that calcium sparks decayed more quickly in the presence of EPA but not DHA. Sarcoplasmic vesicles containing RyRs were prepared from sheep hearts and RyR activity was determined by either [3H]ryanodine binding or by single-channel recording. Bilayers were formed from phosphatidylethanolamine and phosphatidylcholine dissolved in either n-decane or n-tetradecane. EPA inhibited [3H]ryanodine binding to RyRs in SR vesicles with K I = 40 µM. Poly- and mono-unsaturated free fatty acids inhibited RyR activity in lipid bilayers. EPA (cytosolic or luminal) inhibited RyRs with K I =32 µM and Hill coefficient, n 1 = 3.8. Inhibition was independent of the n-alkane solvent and whether RyRs were activated by ATP or Ca2+. DHA and oleic acid also inhibited RyRs, suggesting that free fatty acids generally inhibit RyRs at micromolar concentrations.

Journal

The Journal of Membrane BiologySpringer Journals

Published: Jan 1, 2003

References

You’re reading a free preview. Subscribe to read the entire article.


DeepDyve is your
personal research library

It’s your single place to instantly
discover and read the research
that matters to you.

Enjoy affordable access to
over 18 million articles from more than
15,000 peer-reviewed journals.

All for just $49/month

Explore the DeepDyve Library

Search

Query the DeepDyve database, plus search all of PubMed and Google Scholar seamlessly

Organize

Save any article or search result from DeepDyve, PubMed, and Google Scholar... all in one place.

Access

Get unlimited, online access to over 18 million full-text articles from more than 15,000 scientific journals.

Your journals are on DeepDyve

Read from thousands of the leading scholarly journals from SpringerNature, Elsevier, Wiley-Blackwell, Oxford University Press and more.

All the latest content is available, no embargo periods.

See the journals in your area

DeepDyve

Freelancer

DeepDyve

Pro

Price

FREE

$49/month
$360/year

Save searches from
Google Scholar,
PubMed

Create lists to
organize your research

Export lists, citations

Read DeepDyve articles

Abstract access only

Unlimited access to over
18 million full-text articles

Print

20 pages / month

PDF Discount

20% off