Pharmacology Adrenergic Agonists

alpha-1 receptors

alpha-1 receptors

these receptors are Gq protein-coupled receptors and are found on vascular smooth muscle cells

alpha-2 receptors

these receptors are Gi protein-coupled receptors located on presynaptic nerve endings

1. Vasoconstriction

2. Pupil Dilation

3. Urinary Retention

4. Glycogenolysis

5. Inhibition of renin release

Name 5 things that happen to the body when alpha-1 receptors are activated

decrease in intracellular cAMP leading to inhibition of norepinephrine release

What happens when alpha-2 receptors are activated?

beta-1 receptors

these beta receptors are found in the cardiomyocytes

beta-2 receptors

these beta receptors are found in bronchial smooth muscle

beta-3 receptors

these beta receptors are found in adipose tissue

1. Heart rate

2. Contractility

3. AV node conduction

When beta-1 receptors are activated on heart muscle cells name 3 things that are increased as a result

1. Renin release

2. Blood pressure

When beta-1 receptors are activated in juxtaglomerular cells, what two things increase as a result

1. Bronchodilation

2. Vasodilation

3. Insulin release

What 3 things are increased when beta-2 receptors are activated?

1. GI motility

2. Labor

What 2 things decrease when beta-2 receptors are activated?

1. Lipolysis

What happens when beta-3 receptors are activated

decreased

Does beta 3 activation results in increased or decreased urination

epinephrine, norepinephrine, dopamine

Name 3 direct acting adrenergic agonists

epinephrine

treats anaphylaxis, causes vasoconstriction and bronchodilation and useful for cardiac arrest

norepinephrine

causes vasoconstriction and is useful for cardiac arrest and hypotensive shock

dopamine

activates cardiac beta-1 receptors

oxymetazoline and phenylephrine

name 2 alpha-1 selective drugs

oxymetazoline

alpha-1A adrenoceptor agonist used to treat nasal congestion, allergic reactions of the eye, and facial erythema associated with rosacea

phenylephrine

alpha-1 adrenergic agonist used in the management of hypotension, generally in the surgical setting associated with the use of anesthetics.

clonidine

alpha-2 adrenergic agonist used to treat hypertension and severe cancer pain, among other conditions, and to treat withdrawal symptoms from various substances. It is also used to aid in the diagnosis of pheochromocytoma and to prevent migraines

dobutamine

stimulates beta-1 receptors of the heart to increase myocardial contractility and stroke volume, resulting in increased cardiac output; short-term treatment of patients with cardiac decompensation due to depressed contractility resulting either from organic heart disease or from cardiac surgical procedures

albuterol

beta-2 receptor agonist provides symptomatic relief and prevention of bronchospasm due to bronchial asthma, chronic bronchitis, reversible obstructive airway disease, and other chronic bronchopulmonary disorders in which bronchospasm is a complicating factor,

terbutaline

beta-2 adrenergic agonist used as a bronchodilator and to prevent premature labor

salmeterol and formoterol

name 2 long acting beta 2 agonists used as a bronchodilator in the management of asthma and COPD.

mirabegron

a beta-3 adrenergic agonist used to treat overactive bladder and neurogenic detrusor overactivity

ephedrine

alpha and beta-adrenergic agonist indicated to treat hypotension under anesthesia, allergic conditions, bronchial asthma, and nasal congestion

pseudoephedrine

alpha and beta adrenergic agonist used to treat nasal and sinus congestion, as well as allergic rhinitis