ANS Sympathetic I

Question 1

Are Sympathomimetics affecting the SNS direct or indirect acting agonists?

Answer 1

BOTH direct and indirect

Question 2

Are sympatholytics affecting the SNS direct or indirect acting?

Answer 2

BOTH direct and indirect

Question 3

What are the sites of drug action on the SNS?

Answer 3

Storage
Release
Receptor
Uptake

Question 4

What is an example of a drug that acts on storage?

Answer 4

Reserpine

Question 5

Where does Bretylium act?

Answer 5

Release

Question 6

What drug acts as an Alpha-1 agonist?

Answer 6

Phenylephrine

Question 7

What drug acts as an Alpha-1 antagonist?

Answer 7

Prasozin

Question 8

What receptor does xylazine and detomidine act as an agonist on?

Answer 8

Alpha-2 receptor

Question 9

What are the antagonists for Alpha-2 receptors?

Answer 9

Yohimbine

Atipamezole

Question 10

What are two agonists for Beta-1 receptors?

Answer 10

Dobutamine

Dopamine

Question 11

What receptor does Atenolol and Metopropolol act as an antagonist on?

Answer 11

Beta-1

Question 12

What are two agonists for Beta-2 receptors?

Answer 12

Salbutamol

Clenbuterol

Question 13

What is the one antagonist for beta-2 receptors?

Answer 13

Propanolol

Question 14

What are some general clinical uses for adrenergic agonists?

Answer 14

Heart disease
Anaphylactic reactions
Obstructive airway disease
Sedation an analgesia

Question 15

What are some general clinical uses for adrenergic antagonists?

Answer 15

Slow the heart
Vasodilation
Reversal of alpha-2 sedation

Question 16

What are direct acting alpha/beta AGONISTS? (catecholamines)

Answer 16

Epinephrine
Norepinephrine
Dopamine
Dobutamine
Isoproterenol
Phenylphrine

Question 17

General characteristics of Catecholamines

Answer 17

• Poorly absorbed after oral administration
• Readily absorbed from the respiratory tract
• SC absorption slow if alpha-1 agonist
• Do NOT readily cross the BBB
• Action terminated by removal from site of action `

Question 18

What drug activates ALL adrenergic receptors?

Answer 18

Epinephrine

Question 19

Is epinephrine administered PO?

Answer 19

No, but is administered IV, IM, SC, inhaled

Question 20

Cardiac arrest, anaphylaxis, vasopressor, inotropic infusion are some systemic uses of what drug?

Answer 20

Epinephrine

Question 21

What are some local uses of Epinephrine?

Answer 21

Used with local anesthetics to produce local vasoconstriction
Topically to treat hemorrhage
Treating glaucoma

Question 22

What receptors does Norepinphrine mostly activate?

Answer 22

Alpha-1, Alpha-2. Beta-1

Question 23

T/F: Dopamine’s effects depend on dose

Answer 23

TRUE

Low dose- dopamine agonist
Medium-low dose - Beta-1 agonist
Medium- high dose - Beta-1 agonist
High dose - Alpha-1 agonist

Question 24

What drug is a synthetic beta-1 agonist?

Answer 24

Dobutamine

Question 25

How are Isoproterenol and Dobutamine given?

Answer 25

IV fusion Side Note: side effects are similar to dopamine

Question 26

Isoproterenol is a _____ Beta agonist.

Answer 26

Selective (beta-1 and Beta-2)

Question 27

Phenylephrine

Answer 27

Direct -acting alpha-1 agonist

Question 28

What are two Direct- acting beta agonists that are non-selective?

Answer 28

Ractopamine | Zilpaterol

Question 29

What receptors do Ractopamine and Zilpaterol act on?

Answer 29

Beta -1,2,3

Question 30

What are "partitioning agents?

Answer 30

Ractopamine and Zilpaterol are examples Increase rate of weight gain, feed efficiency and carcass leanness in food animals

Question 31

What are selective beta-2 agonists generally used for?

Answer 31

Bronchodilators in treatment of asma or COPD, cilia augmenters

Question 32

What are some cautions of beta-2 agonists?

Answer 32

cardiac stimulation, vasodilation, uterine relaxation, nervousness, sweating, Muscle tremors, etc...

Question 33

What drugs are considered ARCI class 3 agents and may be prohibited by some equine associations?

Answer 33

Selective beta-2 agonists

Question 34

How are Albuterol and Salbutamol typically administered?

Answer 34

With an aersol inhaler Fun fact: oral absorption is poor due to the high pKa (9.3) so it is ionized in blood and tissue

Question 35

What drug is a selective beta-2 agonist, available as an oral syrup for use in horses,has no human products approved, and outside the US is used as an adjunct for treatment of equine dystocia, but is not permitted in food animals?

Answer 35

CLENBUTEROL!!

Question 36

What drug has an oral bioavailability in equines

Answer 36

TERBUTALINE!!!

Question 37

What drug was previously used in horses for navicular disease, ocassionally used in cattle as a tocolytic for cesarean operations, fetal manipulation in dystocia, and is a beta-2 agonist that acts a peripheral vasodilator?

Answer 37

ISOXSUPRINE!!!

Question 38

What are Indirect-acting sympathomimetics generally used for?

Answer 38

CNS effects such as: behavior modification

Question 39

What are some mixed (direct and indirect acting) drugs?

Answer 39

Phenylpropanolamine and Ephedrine

Question 40

When is Phenylpropanolamine primarily used?

Answer 40

It's PROIN!! It is used to treat urinary incontinence due to urethral sphincter hypotnous.

Question 41

When phenylpropanolamine is used in combination with Estrogens, is this relationship antagonistic or synergistic?

Answer 41

Synergistic Estrogens will increase alpha-1 receptors in internal sphincter so when used with hormonal therapy it's a good thing!

Question 42

What drug has an indirect increase in NE release, is now OTC in the US, can increase blood pressure, bronchodilation, mydriasis, and Ma Huang is a herb that is similar?

Answer 42

Ephedrine

Question 43

Phenoxybenzamine

Answer 43

Non-specific alpha antagonist Available as oral (10 mg tablets) Used in SA medicine for: - urinary retention due to urethral hypertonicity - Pheochromocytoma

Question 44

What two drugs are used for urinary retention due to urethral hypertonicity?

Answer 44

Prazosin and Phenoxybenzamine

Question 45

What are two non-selective beta- antagonists?

Answer 45

Propanolol and Sotalol

Question 46

What are two selective beta-1 antagonists?

Answer 46

Atenolol Esmolol Metoprolol

Question 47

What is Propanolol generally used to treat?

Answer 47

Tachyarrhythmias - Decrease SA firing and AV conduction

Question 48

In what forms is propanolol available?

Answer 48

Oral or injectible Mostly oral

Question 49

Does propanolol readily cross the BBB?

Answer 49

Yup!

Question 50

What is the t 1/2 of propanolol?

Answer 50

1-2 hours

Question 51

What drug is a beta-1 antagonist, does not cross the BBB as readily, has a longer half life than propanolol, and less effect on beta-2 receptors in lungs?

Answer 51

ATENOLOL

Question 52

What beta-1 antagonists has been used in treatment of methylxanthine toxicity?

Answer 52

Metoprolol

Question 53

What drug is a selective beta-1 blocker, does not cross the BBB, and has a very short duration so it can be used to test response to beta-blockers.

Answer 53

Esmolol

Question 54

What drug is a class III anti-arrhythmic?

Answer 54

Sotalol

Question 55

Reserpine

Answer 55

Blocks NE uptake into vesicles which reduces storage of NE and leads to mediator depletion. Used for calming equines (ex. long-term stall rest)