- A substance produced by the medulla (inside) of the adrenal gland. The name epinephrine was coined in 1898 by the American pharmacologist and physiologic chemist (biochemist) John Jacob Abel who isolated it from the adrenal gland which is located above (epi-) the kidney ("nephros" in Greek). (Abel also crystallized insulin). Technically speaking, epinephrine is a sympathomimetic catecholamine. It causes quickening of the heart beat, strengthens the force of the hearts contraction, opens up the airways (bronchioles) in the lungs and has numerous other effects. The secretion of epinephrine by the adrenal is part of the fight-or-flight reaction. Adrenaline is a synonym of epinephrine and is the official name in the British Pharmacopoeia.
* * *A catecholamine that is the chief neurohormone of the adrenal medulla of most species; also secreted by 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 e. hydrochloride and e. bitartrate, the latter most frequently used in topical preparations. SYN: adrenaline. [epi- + G. nephros, kidney, + -ine]
* * *epi·neph·rine also epi·neph·rin .ep-ə-'nef-rən n a colorless crystalline feebly basic sympathomimetic hormone C9H13NO3 that is the principal blood-pressure-raising hormone secreted by the adrenal medulla, is prepared from adrenal extracts or made synthetically, and is used medicinally esp. as a heart stimulant, as a vasoconstrictor (as to treat open-angle glaucoma and life-threatening allergic reactions and to prolong the effects of local anesthetics), and as a bronchodilator called also adrenaline
* * *n.
* * *epi·neph·rine (ep″ĭ-nefґrin) a catecholamine hormone secreted by the adrenal medulla and a neurotransmitter, released by certain neurons and active in the central nervous system. It is stored in the chromaffin granules and is released in response to hypoglycemia, stress, and other stimuli. It is a potent stimulator of the adrenergic receptors of the sympathetic nervous system and a powerful cardiac stimulant that accelerates the heart rate and increases cardiac output. It also promotes glycogenolysis and exerts other metabolic effects. [USP] a synthetic preparation of the levorotatory form of epinephrine, used topically as a vasoconstricting adjunct to local or regional anesthesia, intravenously as a cardiac stimulant and vasopressor; subcutaneously, intramuscularly, or intravenously as a systemic antiallergic in the treatment of severe allergic reactions; subcutaneously, intramuscularly, intranasally, or by inhalation as a bronchodilator; and topically to the conjunctiva in the treatment of open-angle glaucoma. Called also adrenaline (Great Britain).
Medical dictionary. 2011.