norepinephrine

American  

[nawr-ep-uh-nef-rin, -reen] / ˌnɔr ɛp əˈnɛf rɪn, -rin /

noun

1. Also called noradrenaline.  Physiology. a neurotransmitter, released by adrenergic nerve terminals in the autonomic and possibly the central nervous system, that has such effects as constricting blood vessels, raising blood pressure, and dilating bronchi.

2. Pharmacology. a commercial form of this substance used for emergency treatment of lowered blood pressure.

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norepinephrine British  

/ ˌnɔːrɛpɪˈnɛfrɪn, -riːn /

noun

1. the US name for noradrenaline

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norepinephrine Scientific  

/ nôr′ĕp-ə-nĕf′rĭn /

1. A substance that acts both as a neurotransmitter and hormone, secreted in the central nervous system, at the nerve endings of the sympathetic nervous system, and by the adrenal gland. Norepinephrine is similar to epinephrine in its physiological effects but acts to regulate regular physiologic activity rather than being released in response to stress. Also called noradrenaline. Chemical formula: C ₈ H ₁₁ NO ₃ .

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Etymology

Origin of norepinephrine

First recorded in 1940–45; nor- + epinephrine

Compare meaning

How does norepinephrine compare to similar and commonly confused words? Explore the most common comparisons:

• epinephrine vs. norepinephrine

Example Sentences

This system, which uses the neurotransmitter norepinephrine to regulate cognition and bodily functions, is known to fluctuate during normal sleep.

From Science Daily • Jan. 20, 2026

He began to explore the role of pharmacology in treating depression, and in 1965 published a seminal paper positing that depression arose due to low levels of certain neurochemicals, highlighting the role of one, norepinephrine.

From Salon • May 23, 2025

The pharmacological market is dominated by two classes of drugs known as selective serotonin reuptake inhibitors and serotonin and norepinephrine reuptake inhibitors.

From Slate • Aug. 20, 2024

"Collectively, norepinephrine neurons do a lot of different things," Schwarz explained.

From Science Daily • May 28, 2024

They found that UV exposure raises norepinephrine levels, decreases leptin levels, and induces the browning of subcutaneous fat, thereby increasing energy expenditure.

From Science Daily • May 22, 2024