Biochem/physiol Actions
Nicorandil is a hybrid ATP-sensitive K+ (KATP) channel opener and nicotinamide nitrate NO donor. Nicorandil selectively activates SUR2B- versus SUR2A-containing KATP channels. It enhances endothelial NO synthase expression and protects against ischemic ventricular arrhythmias. By activating potassium channels, and donating nitric oxide to activate the enzyme guanylate cyclase, Nicorandil causes activation of GMP leading to both arterial and venous vasodilatation. Nicorandil is selective for vascular potassium channels, but has no significant action on cardiac contractility and conduction. |