adrenergic agonist


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Related to adrenergic agonist: Adrenergic antagonist

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.

adrenergic agonist

Any of a group of therapeutic agents, e.g. epinephrine, that mimic or stimulate the sympathetic nervous system.
See also: agonist

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.

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
References in periodicals archive ?
The owner reported that the patient was subjected throughout to profound sedation with a combination of two [alpha]-2 adrenergic agonists (xylazine 0.8 mg/kg, IV + detomidine 10 ug/kg, IV).
The authors also offer recommendations for safe practice in obstetrics in light of the teratogenic risk posed by beta 2 adrenergic agonists.
Metaproterenol (Alupent Inhalation Aerosol[R]) is another selective beta-2 adrenergic agonist bronchodilator.
1, chapter 16, P 650-51-alpha adrenergic agonists said that addition of clonidine to epidural or intrathecal drugs prolongs the duration of sensory and motor blockade supporting our study.
The mechanism by which [alpha]-2 adrenergic agonists prolong the motor and sensory block of local anaesthetics maybe an additive or synergistic effect secondary to the different mechanisms of action of local anaesthetics.
An adrenergic agonist also may be a useful add-on medication to treat comorbid tics and residual impulsivity, hyperactivity, or aggression, Dr.
Dexmedetomidine is a highly selective [[alpha].sub.2] adrenergic agonist with an affinity of eight times greater than clonidine.
Dexmedetomidine is a selective alpha 2 adrenergic agonist with analgesic and sedative properties.
Reduction in halothane anesthetic requirement by clonidine: An a adrenergic agonist. Anesth Analg.
Regression analyses controlled for sex, age, current and prior asthma medications, prior oral corticosteroid and short-acting [[beta].sub.2] adrenergic agonist use, and the initial type of index event.