ニコランジル

This chemical does not meet GHS hazard criteria for 1.5% (1 of 66) of reports.

Danger

H302 (98.5%): Harmful if swallowed [Warning Acute toxicity, oral]

P264, P264+P265, P270, P280, P301+P317, P305+P354+P338, P317, P330, and P501 (click each P-code to see the statement)

Aggregated GHS information provided per 66 reports by companies from 7 notifications to the ECHA C&L Inventory. Each notification may be associated with multiple companies.

Drug-Induced Liver Injury Severity and Toxicity (DILIst)

Nicorandil

DILI Positive

DOI:10.1016/j.drudis.2019.09.022

C - Cardiovascular system

QC - Cardiovascular system

Nicorandil is a potassium channel opener with nitrovasodilator (NO donor) actions, making it both an arterial and a venous dilator. It causes sustained dilation of both the arterial resistance and conductive vessels that increases coronary blood flow, however the effect of the drug on coronary arteries does not involve the coronary steal phenomenon. Activation of potassium channels lead to hyperpolarization of the smooth muscle cells, followed by arterial dilation and afterload reduction. Nicorandil is shown to increase pooling in the capacitance vessels with a decrease in preload through relaxing the venous vascular system. Overall, improved blood flow and reduced infarct size are achieved through reduction of end-diastolix pressure and decreased extravascular component of vascular resistance. Open studies showed the effectiveness of nicorandil treatment on various types of angina pectoris.

Nicorandil mediates its therapeutic efficacy via two main mechanisms. Nicorandil is an activator and opener of ATP-sensitive (ATP-dependent) potassium channels (KATP channels) that are composed of Kir6.x-type subunits and sulfonylurea receptor (SUR) subunits. Nicorandil binding sites are located in the sulfonylurea receptor 2 (SUR2) in the ATP-sensitive potassium channel, which are regulatory subunits of the channel that exhibit an ATPase activitiy. There are 2 types of SUR2 subunits (2A/2B) that have identical nucleotide binding domains (NBD), where SUR2A is more predominantly expressed in skeletal and cardiac myocytes and SUR2B in smooth muscle cells. Nicorandil more potently activates SUR2B/Kir6.2 than SUR2A/Kir6.2 channels to cause hyperpolarization. ATP-NBD1 interaction influences the channel signalling by nicorandil, and the response of the channel to nicorandil is also facilitated and heightened by the interaction of ATP or ADP with NBD2. Potentiated activity of ATP-sensitive channels have cardioprotective role by limiting the duration of action potentials and preventing intraceullar calcium overload. This attenuates cellular injury by preserving cellular energetics and ultimately cell survival. KATP channel-dependent membrane hyperpolarization can also lead to vasodilation via reduction in Ca2+ influx through the voltage-gated Ca2+ channels and regulation of intracellular Ca2+ mobilization in smooth muscle cells. Nicorandil contain a nitrate moiety in its structure, making it a good dilator of vascular smooth muscle like other nitroglycerin esters. Direct relaxation of venous vascular system arises from NO-donor mediated stimulation of guanylyl cyclase and increased levels of intracellular cyclic GMP (cGMP). Elevated levels of cGMP contributes to the total relaxing effect of nicorandil at higher concentrations of the drug.

Nicorandil undergoes extensive hepatic metabolism. The main biotransformation pathways of nicorandil are denitration, followed by subsequent nicotinamide metabolism. The main pharmacologically inactive denitrated metabolite 2-nicotinamidoethanol can be detected in the urine. The derivatives formed from the nicotinamide metabolism of denitrated products are nicotinuric acid, nicotinamide, N-methylnicotinamide and nicotinic acid.

Agents used for the treatment or prevention of cardiac arrhythmias. They may affect the polarization-repolarization phase of the action potential, its excitability or refractoriness, or impulse conduction or membrane responsiveness within cardiac fibers. Anti-arrhythmia agents are often classed into four main groups according to their mechanism of action: sodium channel blockade, beta-adrenergic blockade, repolarization prolongation, or calcium channel blockade.

Drugs used in the treatment of acute or chronic vascular HYPERTENSION regardless of pharmacological mechanism. Among the antihypertensive agents are DIURETICS; (especially DIURETICS, THIAZIDE); ADRENERGIC BETA-ANTAGONISTS; ADRENERGIC ALPHA-ANTAGONISTS; ANGIOTENSIN-CONVERTING ENZYME INHIBITORS; CALCIUM CHANNEL BLOCKERS; GANGLIONIC BLOCKERS; and VASODILATOR AGENTS.

Drugs used to cause dilation of the blood vessels.

A group of water-soluble vitamins, some of which are COENZYMES.

Following oral administration, nicorandil is well absorbed from the gastrointestinal tract with the oral bioavailability of 75% with the maximum peak plasma concentration (Cmax) reached within 30-60 minutes. The mean Cmax is Cmax then is approximately 300 ng/ml. Steady-state plasma concentrations of nicorandil usually are reached within approximately 96-120 h after twice daily dosing (10 or 20mg).

The main route of elimination is the kidney with more than 60% of the administered dose was eliminated in the urine 24 hours after dosing. Only approximately 1% of nicorandil is excreted unchanged in the urine, and the remaining compounds are mainly the denitrated metabolite (9%) and its derivatives (e.g. nicotinuric acid 6%, nicotinamide 1%, N-methylnicotinamide < 1% and nicotinic acid < 1%). Less than 2% of administered dose is excreted through the biliary system.

After oral (and i.v.) administration of the drug, the apparent volume of distribution is approximately 1.0-1.4 L/kg body weight.

The total body clearance is approximately 1.15 L/min.