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or epinephrin

[ep-uh-nef-rin, -reen] /ˌɛp əˈnɛf rɪn, -rin/
Biochemistry. a hormone secreted by the adrenal medulla upon stimulation by the central nervous system in response to stress, as anger or fear, and acting to increase heart rate, blood pressure, cardiac output, and carbohydrate metabolism.
Pharmacology. a commercial form of this substance, extracted from the adrenal glands of sheep and cattle, or synthesized: used chiefly as a heart stimulant, to constrict the blood vessels, and to relax the bronchi in asthma.
Also called adrenaline.
Origin of epinephrine
1895-1900; epi- + Greek nephr(ós) kidney + -ine2 Unabridged
Based on the Random House Dictionary, © Random House, Inc. 2018.
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British Dictionary definitions for epinephrine


/ˌɛpɪˈnɛfrɪn; -riːn/
a US name for adrenaline
Word Origin
C19: from epi- + nephro- + -ine²
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition
© William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins
Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
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Word Origin and History for epinephrine

1883, from epi- "upon" + Greek nephros "kidney" (see nephron) + chemical suffix -ine (2). So called because the adrenal glands are on the kidneys.

Online Etymology Dictionary, © 2010 Douglas Harper
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epinephrine in Medicine

epinephrine ep·i·neph·rine or ep·i·neph·rin (ěp'ə-něf'rĭn)

  1. A catecholamine hormone of the adrenal medulla that is the most potent stimulant of the sympathetic nervous system, resulting in increased heart rate and force of contraction, vasoconstriction or vasodilation, relaxation of bronchiolar and intestinal smooth muscle, glycogenolysis, lipolysis, and other metabolic effects. Also called adrenaline.

  2. A white to brownish crystalline compound isolated from the adrenal glands of certain mammals or synthesized and used in medicine as a heart stimulant, vasoconstrictor, and bronchial relaxant.

The American Heritage® Stedman's Medical Dictionary
Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.
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epinephrine in Science
A hormone that is secreted by the adrenal gland in response to physical or mental stress, as from fear, and is regulated by the autonomic nervous system. The release of epinephrine causes an increase in heart rate, blood pressure, and respiratory rate. Epinephrine also raises glucose levels in the blood for use as fuel when more alertness or greater physical effort is needed. Also called adrenaline. Chemical formula: C9H13NO3.
The American Heritage® Science Dictionary
Copyright © 2002. Published by Houghton Mifflin. All rights reserved.
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