Pinacidil inhibits the ryanodine‐sensitive outward current and glibenclamide antagonizes its action in cells from the rabbit portal vein

Pinacidil, a potassium-channel opener, inhibited the ryanodine-sensitive oscillatory outward potassium current induced by Ca released from an intracellular store. Glibenclamide, a blocker of the ATP-sensitive K-channel, prevented the action of pinacidil, suggesting the presence of an additional site (to K channels) for the vasodilator actions of pinacidil at which glibenclamide can act as an antagonist.