1. Effects of n-3 fatty acids and acute exercise on endothelium-dependent vasorelaxation in healthy rat aorta
- Author
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E. Heylen, François Guerrero, J. Delarue, Charlotte Corporeau, Jacques Mansourati, Sanéo Thioub, Optimisation des régulations physiologiques (ORPHY (EA 4324)), Institut Brestois Santé Agro Matière (IBSAM), Université de Brest (UBO)-Université de Brest (UBO)-Université de Brest (UBO)-Centre Hospitalier Régional Universitaire de Brest (CHRU Brest), Physiologie et Ecophysiologie des Mollusques Marins (PE2M), Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER), Laboratoire régional de Nutrition Humaine, and Centre Hospitalier Régional Universitaire de Brest (CHRU Brest)
- Subjects
Male ,Vasodilator Agents ,Medicine (miscellaneous) ,Isometric exercise ,MESH: Rats, Sprague-Dawley ,MESH: Physical Conditioning, Animal ,030204 cardiovascular system & hematology ,fish oil ,Muscle, Smooth, Vascular ,MESH: Dose-Response Relationship, Drug ,Rats, Sprague-Dawley ,0302 clinical medicine ,MESH: Fatty Acids, Omega-3 ,Medicine ,Thoracic aorta ,rat ,MESH: Animals ,Aorta ,0303 health sciences ,Nutrition and Dietetics ,MESH: Aorta ,MESH: Muscle, Smooth, Vascular ,Vasodilation ,nifedipine ,medicine.anatomical_structure ,Circulatory system ,MESH: Endothelium, Vascular ,MESH: Nifedipine ,medicine.drug ,medicine.medical_specialty ,Endothelium ,endothelium ,MESH: Rats ,Physical exercise ,acute exercise ,MESH: Vasodilation ,03 medical and health sciences ,Nifedipine ,medicine.artery ,Internal medicine ,Physical Conditioning, Animal ,Fatty Acids, Omega-3 ,[SDV.MHEP.PHY]Life Sciences [q-bio]/Human health and pathology/Tissues and Organs [q-bio.TO] ,Animals ,Unsaturated fatty acid ,030304 developmental biology ,Dose-Response Relationship, Drug ,business.industry ,MESH: Acetylcholine ,acetylcholine ,MESH: Male ,Surgery ,Rats ,MESH: Vasodilator Agents ,Endocrinology ,Endothelium, Vascular ,business - Abstract
The purpose of this study was to determine whether n-3 PUFA result in an effect on endothelial function that is in addition to that of acute exercise. For 4 weeks, male Sprague–Dawley rats were subjected to a diet based on n-3 PUFA or a standard diet. In each diet group, ten rats were submitted to an acute treadmill exercise while the remaining ten acted as sedentary controls. The running speed was progressively increased until the animals were exhausted. Endothelial function was then assessed by measuring isometric tension in rings of the thoracic aorta. In vessels precontracted with 0·1 μm-phenylephrine, responses to acetylcholine (ACh) were significantly improved following acute exercise in all diet groups. When PUFA supplementation was compared to the standard diet no significant difference was found in response to ACh, either at rest or after an acute exercise. Pretreatment of rings with Nω-nitro-l-arginine methyl esther (50 μm) inhibited the ACh-mediated vasorelaxation in all groups. Response to 10 μm-nifedipine, an L-type Ca2+ channel antagonist, was similarly enhanced after acute exercise in both standard and PUFA diets. Furthermore, response to 0·01 μm-nifedipine was significantly higher after acute exercise only in the PUFA diet. In conclusion, in our ‘healthy’ rat model with ‘normal’ baseline endothelial function, acute exercise improves response to ACh while PUFA supplementation alone or in combination with acute exercise has no effect on endothelium-dependent vasorelaxation. However, PUFA may potentiate the acute exercise effect on smooth muscle cell relaxation via L-type Ca2+ channel modifications.
- Published
- 2009