adrenaline

epinephrine

 [ep″ĭ-nef´rin]

a hormone produced by the adrenal medulla; called also adrenaline (British). Its function is to aid in the regulation of the sympathetic branch of the autonomic nervous system. At times when a person is highly stimulated, as by fear, anger, or some challenging situation, extra amounts of epinephrine are released into the bloodstream, preparing the body for energetic action. Epinephrine is a powerful vasopressor that increases blood pressure and increases the heart rate and cardiac output. It also increases glycogenolysis and the release of glucose from the liver, so that a person has a suddenly increased feeling of muscular strength and aggressiveness.ƒ

Some disorders of the adrenal glands, such as addison's disease, reduce the output of epinephrine below normal. By contrast, excessive activity of those glands, as sometimes seen in highly emotional persons, tends to produce tenseness, palpitation, high blood pressure, perhaps diarrhea, and overaggressiveness. Certain adrenal tumors also result in the production of too much epinephrine. Removal of the tumor relieves symptoms.

Epinephrine is also produced synthetically and can be administered parenterally, topically, or by inhalation. It acts as a vasoconstrictor, antispasmodic, and sympathomimetic, and it is used as an emergency heart stimulant as well as to relieve symptoms in allergic conditions such as urticaria (hives), asthma, and other conditions requiring bronchodilation and as a adjunct to local and regional anesthesia. It is the most effective drug for counteracting the lethal effects of anaphylactic shock. It is also used topically in the eye in the treatment of glaucoma.

ep·i·neph·rine

(ep'i-nef'rin),

A catecholamine that is the chief neurohormone of the adrenal medulla of most species; also secreted by certain neurons. The l-isomer is the most potent stimulant (sympathomimetic) of adrenergic α- and β-receptors, 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; used in the treatment of bronchial asthma, acute allergic disorders, open-angle glaucoma, cardiac arrest, and heart block, and as a topical and local vasoconstrictor. Generally used salts are epinephrine hydrochloride and epinephrine bitartrate, the latter most frequently used in topical preparations.
See also: emergency theory, fight or flight response.

Synonym(s): adrenaline

[epi- + G. nephros, kidney, + -ine]

adrenaline

/adren·a·line/ (ah-dren´ah-lin) epinephrine.

adrenaline

(ə-drĕn′ə-lĭn)

n.

See epinephrine.

adrenaline

See epINEPHrine.

adrenaline

A sympathomimetic catecholamine hormone synthesised in the adrenal medulla and released into the circulation in response to hypoglycemia and sympathetic nervous system—i.e., splanchnic nerve stimulation due to exercise and stress; it acts on α- and β-receptors, resulting in vasoconstriction or vasodilation, decreased peripheral blood flow, increased heart rate, increased force of contractility, increased glycogenolysis and increased lipolysis. Pharmacologic doses of epinephrine are used as bronchodilator for acute asthma, to increase blood pressure and in acute myocardial infarctions, to improve myocardial and cerebral blood flow. Adrenaline is the official British pharmacopoeia name for epinephrine.

adrenaline

British for epinephrine, see there.

ep·i·neph·rine

(ep'i-nef'rin)

A catecholamine that is the chief neurohormone of the medulla of the suprarenal gland. The l-isomer is the most potent stimulant (sympathomimetic) of adrenergic α- and β-receptors, 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; used in the treatment of bronchial asthma, acute allergic disorders, open-angle glaucoma, and heart block, and as a topical and local vasoconstrictor.
Synonym(s): adrenaline.

[epi- + G. nephros, kidney, + -ine]

adrenaline

Epinephrine, a HORMONE secreted by the inner part of the ADRENAL GLANDS. It is produced when unusual efforts are required. It speeds up the heart, increases the rate and ease of breathing, raises the blood pressure, deflects blood from the digestive system to the muscles, mobilizes the fuel glucose and causes a sense of alertness and excitement. It has been described as the hormone of ‘fright, fight and flight’. Adrenaline is available for use as a drug. Also known, especially in USA, as epinephrine.

adrenaline

or

epinephrine

a hormone secreted by the medulla (central part) of the ADRENAL GLAND. It prepares the body for emergency action (FIGHT-OR-FLIGHT REACTION); it increases the cardiac frequency, constricts the vessels supplying the skin and gut, increases the blood pressure, increases blood sugar, dilates the blood vessels of the muscles, heart and brain, widens the pupils, and causes hair erection. It is usually secreted with NORADRENALINE, whose effects are similar. Both hormones are also secreted by the ADRENERGIC nerve endings of the sympathetic nervous system.

adrenaline

( epinephrine ) a catecholamine, one of the hormones secreted from the adrenal medulla into the blood stream, in response to stimulation by the sympathetic nervous system, increasing in circumstances requiring urgent and demanding action. Prepares the body for 'fight or flight' or for any other enhanced activity by increasing the heart rate and force, selectively increasing blood flow to muscle and mobilizing glucose from liver glycogen stores. Acts on adrenoceptors via the circulating blood, also as a neurotransmitter but, in mammals, only within the central nervous system.

adrenaline

hormone produced by medulla of the adrenal gland; see epinephrine

adrenaline,

n See epinephrine.

adrenaline (epinephrine) 

A hormone of the adrenal medulla which, instilled in the eye, causes a constriction of the conjunctival vessels, dilates the pupil and diminishes the intraocular pressure. See adrenergic receptors; ocular decongestant; naphazoline; neurotransmitter; noradrenaline (norepinephrine).

ep·i·neph·rine

(ep'i-nef'rin)

A catecholamine that is the chief neurohormone of the adrenal medulla of most species; also secreted by some neurons; used to treat bronchial asthma, acute allergic disorders, open-angle glaucoma, cardiac arrest, and heart block, and as a topical and local vasoconstrictor.
Synonym(s): adrenaline.

[epi- + G. nephros, kidney, + -ine]

adrenaline (ədren´əlin),

n the British term for epinephrine.

adrenaline

see epinephrine.