The metabolic syndrome, Type II (non-insulin-dependent) diabetes and obesity are associated with endothelial dysfunction and increased plasma concentrations of NEFAs (non-esterified fatty acids; free fatty acids). The present study was undertaken to define the inhibitory effects of saturated NEFAs on EDR (endothelium-dependent relaxation). Experiments were performed in rings of rabbit aorta to establish (i) dose–response relationships, (ii) the effect of chain length, (iii) the effect of the presence of double bonds, (iv) reversibility and time course of inhibition, and (v) the effect on nitric oxide production. Aortic rings were incubated (1 h) with NEFA–albumin complexes derived from lauric (C12:0), myristic (C14:0), palmitic (C16:0), stearic (C18:0) and linolenic (C18:3) acids. EDR induced by acetylcholine (0.1–10 μmol/l) was measured after pre-contraction with noradrenaline. Inhibition of EDR was dose-dependent (0.5–2 mmol/l NEFA), and the greatest inhibition (51%) was observed with stearic acid (2 mmol/l). Lauric acid had the smallest inhibitory effect. The inhibitory effects were always reversible and were evident after 15 min of incubation. Linolenic acid caused a significantly lower inhibition of EDR than stearic acid. SOD (superoxide dismutase) restored the inhibitory effect caused by NEFAs, suggesting the involvement of ROS (reactive oxygen species) in removing nitric oxide. The nitric oxide concentration measured after exposure of the rings to acetylcholine was lower after incubation with NEFAs than with Krebs buffer alone. This finding is consistent with removal of nitric oxide by ROS. This claim was supported by the demonstration of increased concentrations of nitrated tyrosine in the rings incubated with NEFAs.
Skip Nav Destination
Article navigation
August 2006
-
Cover Image
Cover Image
- PDF Icon PDF LinkTable of Contents
Research Article|
July 13 2006
Effect of fatty acids on endothelium-dependent relaxation in the rabbit aorta
Indika Edirisinghe;
Indika Edirisinghe
1Division of Cardiovascular Medicine, University of California, One Shields Avenue, TB172, Biolettie Way, Davis, CA 95616, U.S.A.
Search for other works by this author on:
Kellie McCormick Hallam;
Kellie McCormick Hallam
1Division of Cardiovascular Medicine, University of California, One Shields Avenue, TB172, Biolettie Way, Davis, CA 95616, U.S.A.
Search for other works by this author on:
C. Tissa Kappagoda
1Division of Cardiovascular Medicine, University of California, One Shields Avenue, TB172, Biolettie Way, Davis, CA 95616, U.S.A.
Correspondence: Dr C. Tissa Kappagoda (email [email protected]).
Search for other works by this author on:
Publisher: Portland Press Ltd
Received:
January 03 2006
Revision Received:
February 13 2006
Accepted:
March 09 2006
Accepted Manuscript online:
March 09 2006
Online ISSN: 1470-8736
Print ISSN: 0143-5221
The Biochemical Society
2006
Clin Sci (Lond) (2006) 111 (2): 145–151.
Article history
Received:
January 03 2006
Revision Received:
February 13 2006
Accepted:
March 09 2006
Accepted Manuscript online:
March 09 2006
Citation
Indika Edirisinghe, Kellie McCormick Hallam, C. Tissa Kappagoda; Effect of fatty acids on endothelium-dependent relaxation in the rabbit aorta. Clin Sci (Lond) 1 August 2006; 111 (2): 145–151. doi: https://doi.org/10.1042/CS20060001
Download citation file:
Sign in
Don't already have an account? Register
Sign in to your personal account
You could not be signed in. Please check your email address / username and password and try again.
Could not validate captcha. Please try again.