norepinephrine

enUK

norepinephrine

(nôr'ĕpīnĕf`rən), a neurotransmitterneurotransmitter,
chemical that transmits information across the junction (synapse) that separates one nerve cell (neuron) from another nerve cell or a muscle. Neurotransmitters are stored in the nerve cell's bulbous end (axon).
..... Click the link for more information. in the catecholaminecatecholamine
, any of several compounds occurring naturally in the body that serve as hormones or as neurotransmitters in the sympathetic nervous system. The catecholamines include such compounds as epinephrine, or adrenaline, norepinephrine, and dopamine.
..... Click the link for more information. family that mediates chemical communication in the sympathetic nervous system, a branch of the autonomic nervous system. Like other neurotransmitters, it is released at synaptic nerve endings to transmit the signal from a nerve cell to other cells. Norepinephrine is almost identical in structure to epinephrineepinephrine
, hormone important to the body's metabolism, also known as adrenaline. Epinephrine, a catecholamine, together with norepinephrine, is secreted principally by the medulla of the adrenal gland.
..... Click the link for more information. , which is released into the bloodstream from the adrenal medulla under sympathetic activation. The sympathetic nervous system functions in response to short-term stress; hence norepinephrine and epinephrine increase the heart rate as well as blood pressure. Other actions of norepinephrine include increased glycogenolysis (the conversion of glycogenglycogen
, starchlike polysaccharide (see carbohydrate) that is found in the liver and muscles of humans and the higher animals and in the cells of the lower animals. Chemically it is a highly branched condensation polymer of glucose; it is readily hydrolyzed to glucose.
..... Click the link for more information. to glucoseglucose,
dextrose,
or grape sugar,
monosaccharide sugar with the empirical formula C₆H₁₂O₆ . This carbohydrate occurs in the sap of most plants and in the juice of grapes and other fruits.
..... Click the link for more information. ) in the liver, increased lipolysis (the conversion of fats to fatty acids; see fats and oilsfats and oils,
group of organic substances that form an important part of the diet and also are useful in many industries. The fats are usually solid, the oils generally liquid at ordinary room temperatures.
..... Click the link for more information. ) in adipose (fat) tissue, and relaxation of bronchial smooth muscle to open up the air passages to the lungs. All of these actions represent a mobilization of the body's resources in order to meet the stressful challenge—such a response is often termed the "flight or fight" syndrome.

Norepinephrine

(also noradrenaline, arterenol, 3,4-dihydroxyphenylethanolamine), a biologically active catecholamine. Norepinephrine has the following structure:

In animals and man, norepinephrine is in part produced by the chromaffin cells of the adrenal medulla, but it is mostly secreted by the adrenergic nerve elements of the sympathetic nervous system, where it serves as a chemical transmitter, or mediator substance, in nerve excitation. Judging by its action on the heart, blood vessels, smooth muscles, and carbohydrate metabolism, norepinephrine possesses the properties of hormones and is similar to its N-methyl derivative—adrenaline. The level of norepinephrine in the blood, organs, and excretions of the body is an indicator of the tone and reactivity of the sympathetic nervous system.

Norepinephrine can be produced synthetically. It is used in medicine to treat such conditions as low blood pressure, collapse, shock, and hemorrhage.

norepinephrine

[‚nȯr·ep·ə′ne·frən] (biochemistry) C₈H₁₁O₃N A hormone produced by chromaffin cells of the adrenal medulla; acts as a vasoconstrictor and mediates transmission of sympathetic nerve impulses. Also known as noradrenaline.

norepinephrine

enUK

norepinephrine

[nor″ep-ĭ-nef´rin] a catecholamine that is the neurotransmitter of most sympathetic postganglionic neurons and also of certain tracts in the central nervous system. It is also a neurohormone stored in the chromaffin granules of the adrenal medulla and released in response to sympathetic stimulation, primarily in response to hypotension. It produces vasoconstriction, an increase in heart rate, and elevation of blood pressure. It is administered intravenously in the form of the bitartrate salt as a vasopressor to restore blood pressure in certain cases of acute hypotension and to improve cardiac function during decompensation associated with congestive heart failure or cardiovascular surgery. Called also noradrenaline.

nor·ep·i·neph·rine (NE),

(nōr'ep-i-nef'rin), A catecholamine hormone the natural form of which is d, although the l form has some activity; the base is considered to be the postganglionic adrenergic mediator, acting on α and β receptors; it is stored in chromaffin granules in the adrenal medulla in much smaller amounts than epinephrine and secreted in response to hypotension and physical stress; in contrast to epinephrine it has little effect on bronchial smooth muscle, metabolic processes, and cardiac output, but has strong vasoconstrictive effects and is used pharmacologically as a vasopressor, primarily as the bitartrate salt. Synonym(s): levarterenol, noradrenaline

norepinephrine

(nôr′ĕp-ə-nĕf′rĭn)n. A substance, C₈H₁₁NO₃, both a hormone and neurotransmitter, that is secreted by the adrenal medulla and the nerve endings of the sympathetic nervous system and causes vasoconstriction and increases in heart rate, blood pressure, and the sugar level of the blood. Also called noradrenaline.

nor·ep·i·neph·rine

(nōr'ep-i-nef'rin) A catecholamine hormone, acting on α- and β-receptors; it is stored in chromaffin granules in the medulla of suprarenal gland in much smaller amounts than epinephrine and secreted in response to hypotension and physical stress; used pharmacologically as a vasopressor.
Synonym(s): noradrenaline.

Norepinephrine

Norepinephrine is a hormone secreted by certain nerve endings of the sympathetic nervous system, and by the medulla (center) of the adrenal glands. Its primary function is to help maintain a constant blood pressure by stimulating certain blood vessels to constrict when the blood pressure falls below normal.Mentioned in: Antidepressant Drugs, SSRI, Catecholamines Tests, Shy-Drager Syndrome, Weight Loss Drugs

noradrenaline (norepinephrine)

A neurohumoral transmitter for most postganglionic sympathetic fibres. It is produced with adrenaline (epinephrine) in the adrenal medulla. It is a powerful excitator of α-adrenergic receptors. See adrenaline (epinephrine); adrenergic receptors; mydriatic; neurotransmitter.

nor·ep·i·neph·rine

(nōr'ep-i-nef'rin) Catecholamine hormone with strong vasoconstrictive effects; used pharmacologically as a vasopressor, primarily as the bitartrate salt.

norepinephrine

nor·ep·i·neph·rine

norepinephrine

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norepinephrine

norepinephrine

norepinephrine

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nor·ep·i·neph·rine (NE),

norepinephrine

nor·ep·i·neph·rine

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noradrenaline (norepinephrine)

nor·ep·i·neph·rine

norepinephrine

Synonyms for norepinephrine

noun a catecholamine precursor of epinephrine that is secreted by the adrenal medulla and also released at synapses

Synonyms

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