Norepinephrine

norepinephrine

type of chemical entity

Subclass of	catecholamine, phenethylamine alkaloid
Get use	Medication
Stereoisomer of	(+)-norepinephrine
Chemical formula	C₈H₁₁NO₃
Canonical SMILES	C1=CC(=C(C=C1C(CN)O)O)O
Isomeric SMILES	C1=CC(=C(C=C1[C@H](CN)O)O)O
Active ingredient in	Levophed
World Health Organisation international non-proprietary name	norepinephrine
Medical condition treated	neurogenic shock
Pregnancy category	Australian pregnancy category B3, US pregnancy category C
Subject has role	alpha-adrenergic agonist, sympathomimetic drug, vasoconstrictor agents, neurotransmitter
Used by	norepinephrine

Norepinephrine (NE), dem sanso call noradrenaline (NA) anaa noradrenalin, be an organic chemical insyd de catecholamine family wey dey function insyd de brain den body as a hormone, neurotransmitter den neuromodulator. De name "norepinephrine" (from Ancient Greek ἐπῐ́ (epí), "upon", den νεφρός (nephrós), "kidney") usually be preferred insyd de United States, whereas "noradrenaline" (from Latin ad, "near", den ren, "kidney") be more commonly used insyd de United Kingdom den de rest of de world. "Norepinephrine" sanso be de international nonproprietary name dem give to de drug. Regardless of wich name be used for de substance einself, parts of de body wey dey produce anaa be affected by am be referred to as noradrenergic.

De general function of norepinephrine be to mobilize de brain den body give action. Norepinephrine release be lowest during sleep, wey dey rise during wakefulness, den dey reach much higher levels during situations of stress anaa danger, insyd de so-called fight-or-flight response. Insyd de brain, norepinephrine dey increase arousal den alertness, dey promote vigilance, dey enhance formation den retrieval of memory, den dey focus attention; e sanso dey increase restlessness den anxiety. Insyd de rest of de body, norepinephrine dey increase heart rate den blood pressure, dey trigger de release of glucose from energy stores, dey increase blood flow to skeletal muscle, dey reduce blood flow to de gastrointestinal system, den dey inhibit voiding of de bladder den gastrointestinal motility.

Insyd de brain, noradrenaline be produced insyd nuclei wey be small yet exert powerful effects on oda brain areas. De most important of dese nuclei be de locus coeruleus, locate insyd de pons. Outsyd de brain, norepinephrine be used as a neurotransmitter by sympathetic ganglia locate near de spinal cord anaa insyd de abdomen, as well as Merkel cells locate insyd de skin. E sanso release directly into de bloodstream by de adrenal glands. Regardless of how den wer e be released, norepinephrine dey act on target cells by binding to den activating adrenergic receptors wey locate on de cell surface.

A variety of medically important drugs work by altering de actions of noradrenaline systems. Noradrenaline einself be widely used as an injectable drug give de treatment of critically low blood pressure. Stimulants often dey increase, dey enhance, anaa otherwise dey act as agonists of norepinephrine. Drugs such as cocaine den methylphenidate dey act as reuptake inhibitors of norepinephrine, as do sam antidepressants, such as those insyd de SNRI class. One of de more notable drugs insyd de stimulant class be amphetamine, wich dey act as a dopamine den norepinephrine analog, reuptake inhibitor, as well as an agent wey dey increase de amount of global catecholamine wey dey signal thru out de nervous system by reversing transporters insyd de synapses. Beta blockers, wich dey counter sam of de effects of noradrenaline by blocking beta-adrenergic receptors, sam times be used to treat glaucoma, migraines den a range of cardiovascular diseases. β1Rs preferentially dey bind epinephrine, along plus norepinephrine to a lesser extent den dey mediate sam of dema cellular effects insyd cardiac myocytes such as increased positive inotropy den lusitropy. β-blockers dey exert dema cardioprotective effects thru decreasing oxygen demand insyd cardiac myocytes; dis be accomplished via decreasing de force of contraction during systole (negative inotropy) den dey decrease de rate of relaxation during diastole (negative lusitropy), thus reducing myocardial energy demand wich be useful in treating cardiovascular disorders wey be accompanied by inadequate myocardial oxygen supply. Alpha blockers, wich dey counter de effects of noradrenaline on alpha-adrenergic receptors, occasionally be used to treat hypertension den psychiatric conditions. Alpha-2 agonists often get a sedating den antihypertensive effect den commonly be used as anesthesia enhancers insyd surgery, as well as insyd treatment of drug anaa alcohol dependence. For reasons wey still be unclear, sam Alpha-2 agonists, such as guanfacine, sanso be shown to be effective insyd de treatment of anxiety disorders den ADHD. Chaw important psychiatric drugs dey exert strong effects on noradrenaline systems insyd de brain, wey dey result in effects wey fi be helpful anaa harmful.