adrenaline

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The so-called ‘fight or flight’ hormone secreted by the inner part of the adrenal gland. It prepares the body for action by its stimulatory effects on muscles, circulation, and carbohydrate and fat metabolism. Adrenaline increases heart rate, the depth and rate of breathing, and metabolic rate. It also improves the force of muscular contractions and delays the onset of fatigue. Its actions oppose those of insulin. Adrenaline accelerates fat mobilization and encourages the conversion of glycogen to glucose.

Adrenaline and adrenaline-related drugs are sometimes used in sport as stimulants. Although these drugs can improve performance, they may produce harmful side-effects such as heart beat irregularities. Consequently, they are on the International Olympic Committee's list of banned substances.

Adrenaline (also called epinephrine), along with noradrenaline (norepinephrine) and dopamine, are catecholamines (substances containing a dihydroxy phenyl grouping with the hydroxy groups in adjacent positions). All three are released at some nerve terminals to act as neurotransmitters, but adrenaline is also found in the adrenal medulla and in chromaffin cells and can be released from these sites into the circulating blood to have effects throughout the body. Adrenaline is synthesized in the adrenal medulla by the methylation of noradrenaline, and both compounds are released from the gland together. Release of adrenal medullary catecholamines is caused by stressful stimuli, acting via the sympathetic nervous system in the so-called flight, fright, and fight phenomenon. Release of adrenaline prepares the individual to deal with the stress; heart rate and force are increased, blood pressure rises, and blood flow to the skeletal and cardiac muscles is increased, while blood flow to the less essential areas (e.g. gut, skin) is decreased. Adrenaline also mobilizes glycogen energy stores from the liver to increase blood glucose.

— Alan W. Cuthbert.

See also adrenal glands; autonomic nervous system.

epinephrine

A hormone secreted by the adrenal medulla. It has wide-ranging effects on muscles, the circulatory system, and carbohydrate metabolism, preparing the body for action or what is commonly referred to as the ‘flight or fight’ response. Adrenaline increases heart rate, depth and rate of breathing, metabolic rate, and the conversion of glycogen to glucose. It also improves the force of muscle actions and delays the onset of fatigue. Adrenaline is a stimulant, a group of pharmacological agents many of which are on the World Anti-Doping Agency's 2005 list of substances prohibited in-competition. However, the use of adrenaline associated with local anaesthetic agents or by local administration (e.g. nasal or opthalmogic) is not prohibited.

Adrenaline

(uh-dren-l-in)

A hormone secreted by the adrenal glands that helps the body meet physical or emotional stress (see endocrine system).

Adrenaline plays a very large role in the fight or flight reaction, which refers to the various processes that occur within the body when it is confronted with some form of mental or physical stress.

Figuratively, the term adrenaline is used in speaking of a high state of excitement: “When the race began, the adrenaline really started pumping.”

(epinephrine)
One of the two main hormones released by the medulla of the adrenal gland, the other being the related noradrenaline. It produces effects similar to the stimulation of the sympathetic nervous system, increasing heart activity and muscular action, generally preparing the body for 'fright, flight, or fight', hence the oft-quoted need for sportsmen 'to get their adrenaline going'.

(Published 1987)

See neurotransmitters and neuromodulators.

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IN BRIEF: n. - A catecholamine secreted by the body in response to stress

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(ədren′əlin)
n

The British term for epinephrine.

Dansk (Danish)
n. - adrenalin

Nederlands (Dutch)
adrenaline

Français (French)
n. - adrénaline, (fig) pouls

Deutsch (German)
n. - Adrenalin

Ελληνική (Greek)
n. - (βιολ.) αδρεναλίνη, επινεφριδίνη

Italiano (Italian)
adrenalina

Português (Portuguese)
n. - adrenalina (f) (Quím.) (Med.)

Русский (Russian)
адреналин

Español (Spanish)
n. - adrenalina

Svenska (Swedish)
n. - adrenalin

中文（简体）(Chinese (Simplified))
肾上腺素

中文（繁體）(Chinese (Traditional))
n. - 腎上腺素

한국어 (Korean)
n. - 아드레날린(부신의 주성분)

日本語 (Japanese)
n. - アドレナリン

العربيه (Arabic)
‏(الاسم) أنزيم ألأدرينالين‏

עברית (Hebrew)
n. - ‮הורמון המיוצר ע"י בלוטות בגוף וגורם להתרגשות ולגירוי, הורמון המופק מחיות ומשמש כחומר ממריץ, אדרנלין (הורמון)‬

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