%0 Journal Article %T Role of the potassium channels in vasorelaxant effect of asafoetida essential oil %J Avicenna Journal of Phytomedicine %I Mashhad University of Medical Sciences %Z 2228-7930 %A Esmaeili, Hassan %A Esmailidehaj, Mansour %A Entezari Zarch, Somayeh %A Azizian, Hossein %D 2020 %\ 07/01/2020 %V 10 %N 4 %P 407-416 %! Role of the potassium channels in vasorelaxant effect of asafoetida essential oil %K asafoetida essential oil %K Potassium channels %K aorta %K Rats %R 10.22038/ajp.2020.41755.2401 %X Objective: In a previous work, we showed that asafoetida essential oil (AEO), from oleo-gum resin of Ferula asafoetida L. from the Apiaceae family, has a vasodilatory effect. This effect was both endothelium-dependent and endothelium-independent. The present study was designed to determine whether potassium channels and intracellular calcium release contribute to AEO-induced vasodilation. Materials and Methods: Rats' thoracic aorta were isolated and denuded. Following induction of contraction by potassium chloride (60 mM), concentration-response curve was plotted by the cumulative addition of AEO (0.625-80 µl/l to the medium of rings. The vasodilatory effect of AEO was assessed before and after addition of phenylephrine and potassium channel blockers (including barium chloride (BC), 4-aminopyridine (4A) and glibenclamide (Gl)). Results: AEO relaxed the precontracted rings in a concentration-dependent manner (IC50=23 µl/l). All potassium channel blockers significantly attenuated the vasodilatory activity of AEO when they were added to rings medium before addition of KCl (p<0.01, 4A and Gl groups and p< 0.001, BC group vs. control group) but not after that. In contrast to K channel blockers, adding AEO before or after phenylephrine, the tension was reduced significantly (p Conclusion: The findings of this study indicated that the vasodilatory effect of AEO on denuded-endothelium aortic ring was mediated through activation of potassium channels and reduced intracellular calcium release. %U https://ajp.mums.ac.ir/article_14791_c0a5e6e3ccb3ffe0c526e36e08242cea.pdf