title: The Role of Potassium Channels in the Vasodilatation Induced by Resveratrol and Naringenin in Isolated Human Umbilical Vein.
abstract: Preclinical Research Potassium (K+) channels have a key role in the maintenance of smooth muscle tone; a variety of agonists can modify the tone by altering K+-channel activity. The aim of this study was assess the effects of the phenols, resveratrol, and naringenin on K+-channels of the vascular smooth muscle. Segments of human umbilical vein (HUV) without endothelium were precontracted using serotonin (100 μM) or 100 mM K+to derive cumulative concentration-response curves using increasing concentrations of resveratrol or naringenin. K+-channel inhibitors were added in the bath before resveratrol (1-100 μM) or naringenin (0.01-1 mM) in assess the role of K+-channels in their effects on HUV precontracted by serotonin. 4-Aminopiridine (4-AP; 1 mM), a nonselective blocker of voltage-dependent, tetraethylammonium (TEA; 1 mM) and barium chloride (1 mM), a nonselective blocker of Ca2+-dependent and inward rectifier K+-channels (respectively) induced significant shifts to the right (P < 0.05) of resveratrol. concentration-response curves. The effect of naringenin was antagonized by 4-AP (1 mM). 4-AP-, TEA-, and barium chloride-sensitive K+-channels are probably involved in the resveratrol vasodilatatory effect, while naringenin seems to affect 4-AP-sensitive K+-channels. However, other mechanisms of vasodilation induced by polyphenols could not be excluded. Drug Dev Res, 2015. © 2015 Wiley Periodicals, Inc.
authors.affiliation: Department of Pharmacology, Clinical Pharmacology and Toxicology, Faculty of Medicine, University of Belgrade, 11000, Belgrade, Serbia.
authors.forename: Dragana
authors.initials: D
authors.lastname: Protić
authors.forename: Nebojša
authors.initials: N
authors.lastname: Radunović
authors.forename: Svetlana
authors.initials: S
authors.lastname: Spremović-Rađenović
authors.forename: Vladimir
authors.initials: V
authors.lastname: Živanović
authors.forename: Helmut
authors.initials: H
authors.lastname: Heinle
authors.forename: Aleksandar
authors.initials: A
authors.lastname: Petrović
authors.forename: Ljiljana
authors.initials: L
authors.lastname: Gojković-Bukarica
keywords: human umbilical vein; naringenin; polyphenols; potassium channels; resveratrol