Effects of dexmedetomidine on isolated rat mesenteric arterial rings / 西安交通大学学报(医学版)

ABSTRACT

Objective To investigate the dilating effect of dexmedetomidine (DEX)on isolated vascular smooth muscles and to explore the mechanism.Methods Tension of isolated mesenteric arterial rings of male Sprague-Dawley rats was recorded.The effects of DEX on the rings and the effects of DEX on vascular reaction induced by various drugs were recorded. Results DEX completely relaxed the contraction induced by phenylephrine (PE)and KCl in a concentration-dependent manner in endothelium intact mesenteric arterial rings in rats.The vasodilating effect of DEX was increased by sodium nitroprusside.In phenylephrine (10-5 mol/L)based on pre-vasoconstriction,adding acetylcholine could not suppress DEX’s vasodilating effect.Vasodilation was not related to the endothelial cells.In physiological saline solution without calcium,DEX significantly inhibited the contraction induced by addition of CaCl2 .Conclusion DEX can induce vasodilation in a concentration-dependent manner,which is not dependent on the endothelial cells.