Norepinephrine
- L-( -)- noradrenaline
- (R ) -norepinephrine
- (L ) - Norepinephrine
- Levarterenol
- (R ) -3,4 -dihydroxyphenyl ethanolamine
- (R )-2- amino-1- (3,4- dihydroxyphenyl ) ethanol
- (R) -4 - (2- amino-1- hydroxyethyl) -1,2- benzenediol
- 4 - [( 1R )-2 -amino-1 -hydroxyethyl ] benzene -1 ,2 -diol (IUPAC)
- 51-41-2 L
- 138-65-8 DL
- 51-40-1 ( anhydrous tartrate)
- 69815-49-2 ( tartrate monohydrate)
- 329-56-6 (hydrochloride)
C01CA03
Colorless crystals
- Neurotransmitter
- Hormone
- 217-218 ° C ( decomposition)
- 102-104 ° C ( tartrate) (decomposition)
- 145.2 to 146.4 ° C ( hydrochloride) (decomposition)
Practically insoluble in water, ethanol and diethyl ether
Risk
0.55 mg · kg -1 ( LD50, mouse, i.v.)
Template: Infobox chemical / molecular formula search available
Noradrenaline or norepinephrine ( INN) is a neurotransmitter and a hormone. It is produced by the body in the adrenal medulla and the locus coeruleus. It is related to adrenalin and stimulates the cardiovascular system. Norepinephrine contributes towards the adrenaline is not a methyl group (- CH3 ) at its amino group. Therefore, norepinephrine and epinephrine show partly physiologically different effects.
A pathologically increased concentration of norepinephrine in the blood is found in the syndrome of heart failure.
- 3.1 Contraindications
Chemistry
Norepinephrine heard, such as adrenalin and dopamine, to the group of catecholamines. Its natural stereoisomer is L-( -)- noradrenaline [ Synonym: (R ) -norepinephrine ], and its enantiomer D-( ) -norepinephrine [ Synonyms: ( S)- noradrenaline ] is physiologically insignificant.
Function
Effect as hormone
Norepinephrine is produced in addition to the adrenaline hormone in the adrenal glands and in the blood ( flight reflex ) cast. It acts predominantly on the arterioles and leads via activation of adrenergic receptors to a narrowing of these vessels and thus to an increase in blood pressure.
Effect as a neurotransmitter
The main function of norepinephrine is its role as a neurotransmitter in central nervous system and the sympathetic nervous system. Norepinephrine This differs from adrenaline, which has only a minor role neurotransmitters.
Norepinephrine is released in the peripheral nervous system of the sympathetic nerve fibers. It is a transmitter substance ( neurotransmitter ) of the postganglionic synapses of the sympathetic nervous system and unfolds largely the same effect as adrenaline. The elimination of noradrenaline from the synaptic cleft occurs mainly by reuptake into the presynaptic cell via the transporter, but can also be enzymatically inactivated. Norepinephrine reuptake inhibitors lead to an increase in norepinephrine concentration and thus to an increase in sympathetic tone.
In the locus coeruleus, a relatively small, dark-colored cell group in the anterior fourth ventricle, a portion of the bridge ( pons), a large part of noradrenaline in the CNS is produced. Benzodiazepines reduce the activity of the locus coeruleus and thus reduce the transport of noradrenaline forebrain.
Biosynthesis
The production of noradrenaline occurs in the adrenal glands and in the nervous system of dopamine by the enzyme Dopaminhydroxylase. As a cofactor and electron Vitamin C plays a role.
Norepinephrine as a drug
Norepinephrine is used as an emergency drug in intensive care. It does a good job in the treatment of the following symptoms:
- Anaphylactic shock
- Hypotension
- Cardiogenic shock
- Septic shock
- Poisoning with vasodilation
It is administered intravenously while mostly using a syringe pump. Norepinephrine should be dosed as low as possible, since it makes the pumping action of the heart. The primary outcome measure of the dosage is adequate renal excretion. Most noradrenaline is combined with a relatively high intake of fluids to replenish the intravascular volume.
Local is the drug for the prevention of bleeding in surgery usually used together with a local anesthetic. As an alternative, one can use adrenaline, particularly when the heart rate is low.
Contraindications
Noradrenaline may not or only very cautiously be applied under the following conditions:
- High blood pressure ( hypertension )
- Cor pulmonale
- Angle-closure glaucoma
- Hyperthyroidism
- Pheochromocytoma
- Severe atherosclerosis with stenosis
- Severe coronary artery disease or severe cardiac insufficiency
- Severe renal impairment
- Supraventricular tachycardia
- Tachyarrhythmia
- Enlargement of the prostate with residual urine
Trade names
Monopreparations: Norepinephrine (D), as well as a generic (CH) Combination preparations: Scandonest (CH)