title: Pharmacological characteristics of the inhibitory effects of docosahexaenoic acid on vascular contractions studied in rat mesenteric artery.
abstract: OBJECTIVE
  Effects of docosahexaenoic acid (DHA) on blood vessel contractions to various constrictors were investigated in rat mesenteric artery and compared with those of eicosapentaenoic acid (EPA) and linoleic acid (LA).
  
  
  METHODS
  Tension changes in mesenteric ring segments were isometrically recorded.
  
  
  RESULTS
  On sustained contractions induced by a thromboxane A₂ mimetic (U46619), DHA exerted a strong inhibitory effect. This inhibitory effect of DHA on U46619 appeared both in endothelium-intact and endothelium-denuded preparations. Although the inhibitory effect of DHA on prostaglandin F₂α (PGF₂α)-induced contractions was also significant, contractions to phenylephrine (PE) and high-KCI were not affected by DHA. As well as DHA, EPA strongly diminished U46619- and PGF₂α-induced contractions without showing a substantial inhibition of PE- and high-KCl-induced contractions. By contrast, LA did not show any significant inhibitory effects on any contractions. The DHA-induced inhibitory actions exerted on U46619 and PGF₂α also emerged if ring preparations were pretreated with this ω-3 polyunsaturated fatty acid (PUFA).
  
  
  CONCLUSIONS
  DHA and EPA are found to more pronouncedly inhibit prostanoid receptor-mediated contractions than other constrictor responses of the mesenteric artery via endothelium-independent mechanisms. These inhibitory effects of ω-3 PUFAs on prostanoid receptor-mediated contractions may partly underlie the mechanisms by which these ω-3 PUFAs elicit protective actions against circulatory disorders.
authors.affiliation: Department of Chemical Pharmacology, Toho University School of Pharmaceutical Sciences, Funabashi, Japan.
authors.forename: Kyosuke
authors.initials: K
authors.lastname: Sato
authors.forename: Daisuke
authors.initials: D
authors.lastname: Chino
authors.forename: Taiki
authors.initials: T
authors.lastname: Sugimoto
authors.forename: Keisuke
authors.initials: K
authors.lastname: Kanai
authors.forename: Keisuke
authors.initials: K
authors.lastname: Obara
authors.forename: Seiji
authors.initials: S
authors.lastname: Miyauchi
authors.forename: Yoshio
authors.initials: Y
authors.lastname: Tanaka
mesh_terms: D019796:15-Hydroxy-11 alpha,9 alpha-(epoxymethano)prosta-5,13-dienoic Acid / Q000494:pharmacology; D000818:Animals; D015237:Dinoprost / Q000494:pharmacology; D004281:Docosahexaenoic Acids / Q000494:pharmacology*; D015118:Eicosapentaenoic Acid / Q000494:pharmacology; D004730:Endothelium, Vascular / Q000187:drug effects / Q000502:physiology; D066298:In Vitro Techniques; D008041:Linoleic Acids / Q000494:pharmacology; D008297:Male; D008638:Mesenteric Arteries / Q000187:drug effects* / Q000502:physiology; D010656:Phenylephrine / Q000494:pharmacology; D017208:Rats, Wistar; D014661:Vasoconstriction / Q000187:drug effects*; D014662:Vasoconstrictor Agents / Q000494:pharmacology
chemical_list: D008041:Linoleic Acids; D014662:Vasoconstrictor Agents; D010656:Phenylephrine; D004281:Docosahexaenoic Acids; D019796:15-Hydroxy-11 alpha,9 alpha-(epoxymethano)prosta-5,13-dienoic Acid; D015118:Eicosapentaenoic Acid; D015237:Dinoprost