Effects of dietary arachidonic acid supplementation on age-related changes in endothelium-dependent vascular responses.
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.
Nakano
Daisuke
D
Department of Pharmacology, Osaka University of Pharmaceutical Sciences, 4-20-1 Nasahara, Takatsuki, Osaka 569-1094, Japan.
Ishii
Fumie
F
Fujii
Kiwako
K
Ishikura
Yoshiyuki
Y
Akimoto
Kengo
K
Kontani
Masanori
M
Kawashima
Hiroshi
H
Kiso
Yoshinobu
Y
Matsumura
Yasuo
Y
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
D014662:Vasoconstrictor Agents; D014665:Vasodilator Agents; D009599:Nitroprusside; D010656:Phenylephrine; D016718:Arachidonic Acid; D000109:Acetylcholine