title: Effects of dietary arachidonic acid supplementation on age-related changes in endothelium-dependent vascular responses.
abstract: The purpose of the present study was to examine the effects of dietary supplementation of arachidonic acid (ARA) on age-related changes in endothelium-dependent vascular responses. Young male Fisher-344 rats (2-mo-old) and aged rats of the same strain (22-mo-old) were randomly separated into a control diet group (young control, YC; old control, OC) and an ARA-containing diet group (young ARA, YA; old ARA, OA). After a 2-mo feeding period, vascular responses were evaluated using both endothelium-intact and -denuded aortic rings. Phenylephrine (alpha1-adrenoceptor agonist)-induced vasoconstrictor responses in endothelium-intact rings from group OC tended to be augmented compared with those of rings from groups YC and YA, although this augmentation was significantly suppressed by dietary supplementation of ARA. There were no significant differences in vascular responses to phenylephrine in endothelium-denuded rings among groups YC, YA, OC, and OA. Acetylcholine (Ach)-induced, endothelium-dependent vasorelaxation was attenuated in groups OC and OA compared with that in groups YC and YA. ARA supplementation induced slight enhancement of Ach-induced vasorelaxation in aged rats. Ach-induced vasorelaxation correlated very well with aortic ARA concentration in aged rats, but not in young rats. There were no significant differences in endothelium-independent vasodilator responses to sodium nitroprusside in endothelium-denuded rings among groups YC, YA, OC, and OA. These findings suggest that dietary ARA supplementation improves the age-related endothelial dysfunction that leads to various cardiovascular diseases.
authors.affiliation: Department of Pharmacology, Osaka University of Pharmaceutical Sciences, 4-20-1 Nasahara, Takatsuki, Osaka 569-1094, Japan.
authors.forename: Daisuke
authors.initials: D
authors.lastname: Nakano
authors.forename: Fumie
authors.initials: F
authors.lastname: Ishii
authors.forename: Kiwako
authors.initials: K
authors.lastname: Fujii
authors.forename: Yoshiyuki
authors.initials: Y
authors.lastname: Ishikura
authors.forename: Kengo
authors.initials: K
authors.lastname: Akimoto
authors.forename: Masanori
authors.initials: M
authors.lastname: Kontani
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Kawashima
authors.forename: Yoshinobu
authors.initials: Y
authors.lastname: Kiso
authors.forename: Yasuo
authors.initials: Y
authors.lastname: Matsumura
mesh_terms: D000109:Acetylcholine / Q000378:metabolism / Q000494:pharmacology; D000367:Age Factors; D000704:Analysis of Variance; D000818:Animals; D001013:Aorta, Thoracic / Q000187:drug effects / Q000378:metabolism / Q000503:physiopathology; D016718:Arachidonic Acid / Q000378:metabolism / Q000494:pharmacology*; D001835:Body Weight / Q000187:drug effects; D019587:Dietary Supplements; D004305:Dose-Response Relationship, Drug; D004730:Endothelium, Vascular / Q000187:drug effects* / Q000378:metabolism / Q000503:physiopathology*; D008297:Male; D023421:Models, Animal; D009599:Nitroprusside / Q000494:pharmacology; D010656:Phenylephrine / Q000378:metabolism / Q000494:pharmacology; D051381:Rats; D011916:Rats, Inbred F344; D014661:Vasoconstriction / Q000187:drug effects; D014662:Vasoconstrictor Agents / Q000378:metabolism / Q000494:pharmacology; D014664:Vasodilation / Q000187:drug effects; D014665:Vasodilator Agents / Q000378:metabolism / Q000494:pharmacology
chemical_list: D014662:Vasoconstrictor Agents; D014665:Vasodilator Agents; D009599:Nitroprusside; D010656:Phenylephrine; D016718:Arachidonic Acid; D000109:Acetylcholine