adrenergic agonist

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Related to Adrenergics: anticholinergic, Cholinergics

adrenergic agonist

A family of agents which have adrenaline-like effects, acting directly or indirectly on any of the five G-protein-coupled adrenergic receptors: apha1, alpha2, beta1, beta2, beta3.

Actions of adrenergic agonists
alpha1 receptors: Activate phospholipase C (via Gq), increasing protein kinase C activity.
alpha2: receptors Inhibit adenylate cyclase (via G1), decreasing protein kinase A activity.
beta receptors: Activate adenylate cyclase (via Gs), increasing protein kinase A activity.
Segen's Medical Dictionary. © 2012 Farlex, Inc. All rights reserved.

adrenergic agonist

Any of a group of therapeutic agents, e.g. epinephrine, that mimic or stimulate the sympathetic nervous system.
See also: agonist
Medical Dictionary, © 2009 Farlex and Partners

sympathomimetic drugs 

Drugs that produce an effect similar to that obtained by stimulation of the sympathetic nervous system. Some of these predominantly act on the adrenergic alpha-receptors (e.g. noradrenaline (norepinephrine)), while others act on the adrenergic beta-receptors (e.g. isoproterenol). Others have little direct effect on the adrenergic receptors but enhance the release of natural catecholamine from the sympathetic nerve terminals (e.g. amphetamine, phenylpropanolamine). Sympathomimetic drugs are used (1) in the treatment of open-angle glaucoma by decreasing aqueous humour secretion and increase the outflow through the trabecular meshwork thus reducing the intraocular pressure (e.g. adrenaline (epinephrine), apraclonidine, dipivefrine hydrochloride, brimonidine tartrate), (2) dilate the pupil without affecting accommodation (e.g. phenylephrine) and (3) constrict conjunctival blood vessels (e.g. naphazoline, tetrahydrozoline). Syn. adrenergic agonist; adrenergic stimulating agent. See alpha-adrenergic agonist; mydriatic.
Millodot: Dictionary of Optometry and Visual Science, 7th edition. © 2009 Butterworth-Heinemann

ad·re·ner·gic ag·o·nist

(adrĕ-nĕrjik agŏ-nist)
An agent capable of combining with receptors to initiate actions of or like epinephrine.
See: agonist
See also: epinephrine
Medical Dictionary for the Dental Professions © Farlex 2012
References in periodicals archive ?
Adverse Effects of Beta-2 Adrenergic Agonist Inhalers
All beta-2 adrenergic agonist inhalers can stimulate immediate airway hyperactivity which leads to acute bronchospasm.
Whether they are short-acting or long-acting, beta-2 adrenergic agonists can have cardiovascular side effects.
Limited research compares long-acting beta-2 adrenergic inhalers and their cardiovascular side effects.
To reduce blood pressure, beta blocker antihypertensive drugs are intended to inhibit specific, cardioselective, beta-1 adrenergic receptors in the heart and vascular walls.
Beta-2 adrenergic receptors are located in the smooth muscle of the bronchioles, blood vessels, genitourinary tract, uterus, gastrointestinal tract, liver, skeletal muscle, and pancreas.
Patients should not take other sympathomimetic drugs, monoamine oxidase (MAO) inhibitors, or tricyclic antidepressants while taking beta-2 adrenergic agonists.