Adrenergic Agonists Drugs

Question 1

Pargyline

Answer 1

MOA inhibitor

-Potentiates sympathetic response

Question 2

Cocaine, Imipramine

Answer 2

-Blocks accumulation of NE by nerves (potentiates sympathetics)
[Modifies NE transport]

Question 3

Tyramine, Amphetamine, Ephedrine

Answer 3

-Reverse axoplasmic transporter (mimic sympathetic stimulation)
[Modifies NE transport]

Question 4

Reserpine

Answer 4

-blocks vesicular accumulation
(depletes NE)
[Modifies NE transport]

Question 5

Guanethidine, Guanadrel

Answer 5

-releases NE from vesicles (depletes NE)

[Modifies NE transport]

Question 6

Epinephrine

Answer 6

-Activates a1, a2, b1 and b2

[Drug activating adrenergic receptors]

Question 7

NE

Answer 7

-Activates a1, a2, and b1

[Drug activating adrenergic receptors]

Question 8

Isoproterenol

Answer 8

-Activates b1 and b2

[Drug activating adrenergic receptors]

Question 9

Phenylephrine

Answer 9

-Activates a1

[Drug activating adrenergic receptors]

Question 10

Dobutamine

Answer 10

-Activates b1

[Drug activating adrenergic receptors]

Question 11

Albuterol, Metaproterenol, Ritodrine, Terbutaline & Salmeterol

Answer 11

-Activate b2

[Drug activating adrenergic receptors]

Question 12

What does Isoproterenol do to BP?

Answer 12

Decreases

Question 13

What does EPI do to BP?

Answer 13

Increases

Question 14

What does NE do to BP?

Answer 14

Increases

Question 15

What does Phenylephrine do to BP?

Answer 15

Increases

Question 16

How do noncatecholamine sympathomimetics act?

Answer 16

• Phenylethylamines are indirectly acting (they release catecholamines from nerves) - Amphetamine
• Oral activity
• Distribute to brain
• Excretion in urine, not degraded by COMT

Question 17

What do noncatecholamine sympathomimetics rely on?

Answer 17

NE for their activity

Question 18

Since noncatecholamine sympathomimetics rely on NE, they are blocked by:

Answer 18

(1) anything that antagonizes NE

2) Anything that prevents their actions to release NE (Imipramine, Reserpine, Guanethidine

Question 19

What are indirectly acting agents?

Answer 19

Release NE from nerves by reversing the catecholamine axoplasmic uptake pump

• Amphetamine
• Ephedrine
• Pseudoephedrine

Question 20

How does amphetamine act?

Answer 20

Primary effect is to release NE from nerves, increasing BP

• Admin: oral
• Toxicity: CNS stimulation, mydriasis, hypertension, tachycardia, hyperthermia
• Therapeutic uses: narcolepsy, hyperkinetic syndrome and obesity

Question 21

How does Ephedrine act?

Answer 21

Releases NE and has direct effects

• CV: inc. bp via NE release to activate alpha1 and beta1 receptors, also vasodilators by interacting with beta2 receptors
• CNS: smaller effect than amphetamine

Question 22

What are the therapeutic uses of Ephedrine? Admin? Toxicity?

Answer 22

Bronchospasm - cold meds, releases NE to vasoconstrict, reducing mucosal congestion via alpha1, also bronchodilates (beta2) by direct effect

• Toxicity: similar to a combination of EPI and amphetamine
• Admin: oral

Question 23

How is pseudoephedrine used?

Answer 23

(Sudafed)

• Steroisomer of ephedrine commonly used to treat nasal congestion
• Given orally 120 mg twice daily

Question 24

What does stimulation of B1 cause?

Answer 24

Inc. HR
Inc. CO
Inc. contractility

Question 25

What does stimulation of A1 cause?

Answer 25

Inc. constriction
Inc. resistance
Vasoconstricts

Question 26

What does stimulation of B2 cause?

Answer 26

Vasodilates/relaxes

-Also acts in lungs

Question 27

Terazosin?

Answer 27

Alpha1 blocker