alexa Apelin increases contractility in failing cardiac muscle.
Clinical Sciences

Clinical Sciences

Cardiovascular Pharmacology: Open Access

Author(s): Dai T, RamirezCorrea G, Gao WD, Dai T, RamirezCorrea G, Gao WD

Abstract Share this page

Abstract Apelin, a ligand for apelin-angiotension receptor-like 1 (APJ), has recently been shown to be a potent positive inotropic agent in normal hearts. In humans, levels of apelin have been shown to rise in early-stage heart failure and to fall in late-stage heart failure. In this study, we tested the hypothesis that apelin augments contraction directly in failing rat cardiac muscle. Right ventricular heart failure secondary to pulmonary hypertension was induced by exposing the rats to hypoxia (10\% O(2) inhaled air) for 14-16 weeks. Trabeculae were dissected and mounted between a force transducer and a motor arm, superfused with Krebs-Henseleit (K-H) solution (pH 7.4, 22 degrees C), and loaded with fura-2. Both force development and [Ca(2+)](i) transient amplitude increased in a dose-dependent manner in the presence of Apelin-12 (10 approximately 70 nM, [Ca(2+)](o)=0.5 mM) in failing muscles as compared to control (36+/-7\% vs. 7.4+/-5\% at 70 nM, P<0.05). Also, [Ca(2+)](i) transients increased up to 18.4+/-9.5\% as compared to control (4.5+/-1.9\%, P<0.05). The increases in contraction in the presence of apelin were also maintained over a range of external Ca(2+) (0.5-2.0 mM). Steady-state force-[Ca(2+)](i) relation of the failing muscles reveals decreased maximal Ca(2+)-activated force (F(max)) (51.45+/-5.3 vs. 98.5+/-11.5 mN/mm(2), P<0.001), with no changes in Ca(2+) required for 50\% of maximal activation (Ca(50)) (0.45+/-0.07 vs. 0.30+/-0.04 muM, P>0.05) and Hill coefficient (4.60+/-0.73 vs. 3.17+/-0.92, P>0.05). Apelin (70 nM) had no effect on the steady-state force-[Ca(2+)](i) relation in failing muscles (F(max): 63.03+/-3.5 mN/mm(2); Ca(50): 0.50+/-0.08 microM; Hill coefficient: 4.73+/-0.89). These results indicate that apelin exerts a selective positive inotropic action in failing myocardium. The increased force development is the result of increased [Ca(2+)](i) transients rather than changes in myofilament calcium responsiveness.
This article was published in Eur J Pharmacol and referenced in Cardiovascular Pharmacology: Open Access

Relevant Expert PPTs

Relevant Speaker PPTs

Recommended Conferences

Peer Reviewed Journals
 
Make the best use of Scientific Research and information from our 700 + peer reviewed, Open Access Journals
International Conferences 2017-18
 
Meet Inspiring Speakers and Experts at our 3000+ Global Annual Meetings

Contact Us

Agri, Food, Aqua and Veterinary Science Journals

Dr. Krish

agrifoodaquavet@omicsonline.com

1-702-714-7001 Extn: 9040

Clinical and Biochemistry Journals

Datta A

clinical_biochem@omicsonline.com

1-702-714-7001Extn: 9037

Business & Management Journals

Ronald

business@omicsonline.com

1-702-714-7001Extn: 9042

Chemical Engineering and Chemistry Journals

Gabriel Shaw

chemicaleng_chemistry@omicsonline.com

1-702-714-7001 Extn: 9040

Earth & Environmental Sciences

Katie Wilson

environmentalsci@omicsonline.com

1-702-714-7001Extn: 9042

Engineering Journals

James Franklin

engineering@omicsonline.com

1-702-714-7001Extn: 9042

General Science and Health care Journals

Andrea Jason

generalsci_healthcare@omicsonline.com

1-702-714-7001Extn: 9043

Genetics and Molecular Biology Journals

Anna Melissa

genetics_molbio@omicsonline.com

1-702-714-7001 Extn: 9006

Immunology & Microbiology Journals

David Gorantl

immuno_microbio@omicsonline.com

1-702-714-7001Extn: 9014

Informatics Journals

Stephanie Skinner

omics@omicsonline.com

1-702-714-7001Extn: 9039

Material Sciences Journals

Rachle Green

materialsci@omicsonline.com

1-702-714-7001Extn: 9039

Mathematics and Physics Journals

Jim Willison

mathematics_physics@omicsonline.com

1-702-714-7001 Extn: 9042

Medical Journals

Nimmi Anna

medical@omicsonline.com

1-702-714-7001 Extn: 9038

Neuroscience & Psychology Journals

Nathan T

neuro_psychology@omicsonline.com

1-702-714-7001Extn: 9041

Pharmaceutical Sciences Journals

John Behannon

pharma@omicsonline.com

1-702-714-7001Extn: 9007

Social & Political Science Journals

Steve Harry

social_politicalsci@omicsonline.com

1-702-714-7001 Extn: 9042

 
© 2008-2017 OMICS International - Open Access Publisher. Best viewed in Mozilla Firefox | Google Chrome | Above IE 7.0 version