Adrenergic Agonists Overview

These flashcards cover the vocabulary and key concepts related to adrenergic agonists, their mechanisms of action, effects, and clinical applications.

Adrenergic Agonists

Drugs that stimulate adrenergic receptors, mimicking the effects of sympathetic nervous system neurotransmitters.

Sympathomimetics

Agents that mimic the effects of sympathetic nervous system activation.

Catecholamines

A class of compounds including epinephrine and norepinephrine, derived from tyrosine and characterized by a catechol structure.

Epinephrine

A catecholamine hormone that acts on both α and β receptors, used in emergency situations for its bronchodilatory effects.

Noradrenaline

A neurotransmitter that primarily acts on α receptors, increasing peripheral vascular resistance.

Receptors: α1

Adrenergic receptors that cause vasoconstriction and increased peripheral resistance.

Receptors: β1

Adrenergic receptors primarily found in the heart, responsible for increasing heart rate and force of contraction.

Receptors: β2

Adrenergic receptors primarily found in smooth muscles responsible for relaxation and bronchodilation.

Mixed-action agonists

Drugs that have both direct action on adrenergic receptors and enhance the release of norepinephrine.

Tyrosine

An amino acid that is the precursor to catecholamines.

Reserpine

A drug that inhibits the storage of norepinephrine in synaptic vesicles.

Methylation

A chemical process that adds a methyl group to a compound, important in the metabolism of catecholamines.

Baroreceptor reflex

A mechanism that helps regulate blood pressure by using neuronal feedback.

Bronchodilation

The relaxation of bronchial muscles leading to wider air passages, often induced by β2 agonists.

Tachycardia

An increased heart rate, which can result from adrenergic stimulation.

Hypertension

High blood pressure, which can be influenced by adrenergic receptor activity.

Resistant hypertension

High blood pressure that does not respond adequately to standard antihypertensive treatments.

Vasoconstriction

The narrowing of blood vessels, often mediated by α adrenergic receptor activation.

α2 receptors

Presynaptic receptors that inhibit norepinephrine release; involved in negative feedback.

Adverse effects of epinephrine

Include anxiety, headaches, and potential arrhythmias.

Clonidine

An α2-agonist used to treat hypertension and minimize withdrawal symptoms.

Phenylephrine

A selective α1-agonist used as a nasal decongestant and maintains blood pressure.

Amphetamines

CNS stimulants that increase norepinephrine release and are used in ADHD treatment.

Tyramine

A naturally occurring compound that releases stored norepinephrine.

Cocaine

A local anesthetic that blocks norepinephrine uptake; increases sympathetic effects.

Ephedrine

A mixed-action agonist used for its bronchodilator effects and nasal decongestion.

Dobutamine

A synthetic catecholamine that primarily stimulates β1 receptors to increase cardiac output.