epinephrine

ep·i·neph·rine also ep·i·neph·rin   (ěp'ə-něf'rĭn)    n.   A hormone secreted by the adrenal medulla that is released into the bloodstream in response to physical or mental stress, as from fear or injury. It initiates many bodily responses, including the stimulation of heart action and an increase in blood pressure, metabolic rate, and blood glucose concentration. Also called adrenaline. A white to brownish crystalline compound, C9H13NO3, isolated from the adrenal glands of certain mammals or synthesized and used in medicine as a heart stimulant, vasoconstrictor, and bronchial relaxant. [epi- + nephr(o)- + -ine2.]

Main Entry: epi·neph·rine
Variant: also epi·neph·rin /"ep-&-'nef-r&n/
Function: noun
: a colorlesscrystalline feebly basic sympathomimetic hormone C₉H₁₃NO₃ that is the principal blood-pressure-raising hormone secreted by the adrenal medulla, is prepared from adrenalextracts or made synthetically, and is used medicinally especially as a heart stimulant, as a vasoconstrictor in controlling hemorrhages of the skin and in prolonging the effects of local anesthetics,and as a muscle relaxant in bronchial asthma called also adrenaline

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

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.

epinephrine   (ěp'ə-něf'rĭn)  Pronunciation Key  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.

epinephrine

two separate but related hormones secreted by the medulla of the adrenal glands. They are also produced at the ends of sympathetic nerve fibres, where they serve as chemical mediators for conveying the nerve impulses to effector organs. Chemically, the two compounds differ only slightly; and they exert similar pharmacological actions, which resemble the effects of stimulation of the sympathetic nervous system. They are, therefore, classified as sympathomimetic agents. The active secretion of the adrenal medulla contains approximately 80 percent epinephrine and 20 percent norepinephrine; but this proportion is reversed in the sympathetic nerves, which contain predominantly norepinephrine.

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