Receptor sympathomimetic amines

Terbutaline is a synthetic sympathomimetic amine. It is one of the most selective direct-acting stimulants of )32 dr6noreceptors. It stimulates smooth muscle )32-adrenoreceptors in the bronchi, relaxing them and relatively minutely acting on the — receptors of the heart. 

A.M. Lands, A. Arnold, J.P. McAuliff, F.P. Luduena, T.G. Brown, Differentiation of receptor systems activated by sympathomimetic amines. Nature 214 (1967) 597-598. 

Mechanism of Action A sympathomimetic amine that produces CNS and respiratory stimulation, mydriasis, bronchodilation, a pressor response, and contraction of the urinary sphincter Directly effects alpha and beta receptor sites in peripheral system. Enhancesreleaseof norepinephrine by blocking reuptake, inhibiting monoamine oxidase. Therapeutic Effect Increases motor activity, mental alertness decreases drowsiness, fatigue. 

Mechanism of Action A direct-acting sympathomimetic amine that acts on alpha-adrenergic receptors in arterioles of the nasal mucosa to produce constriction. Therapeutic Effect Causes vasoconstriction resulting in decreased blood flow and decreased nasal congestion. 

Weiner, N. (1991) Drugs that inhibit adrenergic nerves and block adrenergic receptors. In Gilman, A. and Goodman, L., eds. Norepinephrine, Epinephrine and the Sympathomimetic Amines, 7th ed. New York The Pharmacological Basis of Therapeutics, pp. 145-180. 

The actions of particular sympathomimetic amine depend on its relative activity at different types of adrenergic receptors. The overall actions are ... 

These are the agents which block the action of sympathetic nerve stimulation and circulating sympathomimetic amines on the beta adrenergic receptors. At the cellular level, they inhibit the activity of the membrane cAMP. The main effect is to reduce cardiac activity by diminishing (3 receptor stimulation in the heart. This decreases the rate and force of myocardial contraction of the heart, and decreases the rate of conduction of impulses through the conduction system. They are classified as in table 3.3.2. 

Phenylephrine is a synthetic sympathomimetic amine structurally similar to epinephrine. It acts primarily on ai receptors and has little or no effect on (3 receptors. A minor part of its pharmacologic effects may be attributed to release of norepinephrine from adrenergic nerve terminals. 

Pseudoephedrine is an orally active sympathomimetic amine exerting its decongestant action by acting directly on a-adrenergic receptors in the respiratory tract mucosa producing vasoconstriction resulting in shrinkage of swollen nasal mucous membranes, reduction of tissue hyperemia, edema, and nasal... 

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