Adrenergics

Question 1

NE synthesis

Answer 1

Tyrosine converted to DA
DA –> NE
NE –> epi (in adrenal medulla)

Question 2

Release, action, and inhib of NE at nerve terminal

Answer 2

Release initiated by Ca, ATP
Inhibit by NE at pre a2 and PGE at pre
Ang II enhances release
MAO and COMT breakdown

Question 3

Guanethidine mechanism

Answer 3

Enters via NET
Concentrates in vesicles
Depletes NE gradually
Old hypertensive

Question 4

Reserpine mech

Answer 4

Enters terminal, blocks VMAT
Depletes NE over time
Empty vesicles
Old hypertensive

Question 5

Amphetamine mechanism

Answer 5

NET substrate
Increases synaptic NE via diffusion
Fast kinetics, inc HR/BP quickly

Question 6

Tyramine mechanism

Answer 6

High dose can cause NE displacement from vesicles (MAO will take care of it, unless person is on MAOI then NE will go into synapse via diffusion and hypertensive crisis occurs)

Question 7

Mechanism of cocaine, imipramine, and atomoxetine (stimulants)

Answer 7

Block NET, leaving NE out in the synapse

Question 8

Phenylephrine mechanism

Answer 8

Alpha agonist

Question 9

Phentolamine mechanism

Answer 9

Alpha antagonist

Question 10

Propanolol mechanism

Answer 10

B antagonist

Question 11

a1 location and adrenergic response

Answer 11

Constriction of all BV
GI/bladder sphincter contraction
Ejaculation/orgasm

Question 12

B1 location and adrenergic response

Answer 12

Heart
Inc HR/contractility
Renin release

Question 13

B2 location and adrenergic response

Answer 13

Skeletal muscle and bronchioles
Dilation of skeletal muscle BV
Bronchodilation

Question 14

Receptors that NE acts on

Answer 14

a1 and B1

Question 15

Receptors that isoproterenol acts on

Answer 15

B1, B2

Question 16

Receptors that epinephrine acts on

Answer 16

low B1/B2

High a1, b1, b2

Question 17

Receptors that dopamine acts on

Answer 17

low: DA, b1, b2
high: ALL

Question 18

Receptor that dobutamine acts on

Answer 18

low = b1
high = a1, b1, b2

Question 19

At low dose, which adrenergic increases contractility without affecting rate?

Answer 19

Dobutamine

Question 20

Affinity for B1 receptor

Answer 20

ISO > epi = NE

Question 21

Affinity for B2 receptor

Answer 21

ISO > epi&raquo_space; NE

Question 22

Affinity for a1 receptor

Answer 22

Epi > NE&raquo_space; ISO

Question 23

Structure: how to increase B receptor affinity

Answer 23

Inc size of amino group

Question 24

Structure: maximum a/B activity conferred by..

Answer 24

OH groups at 3/4

Question 25

Structure: how to increase CNS penetration

Answer 25

Remove hydroxyl group

Question 26

Therapeutic uses of epinephrine

Answer 26

Anaphylactic shock
Asthma, hyper sensitivity
Topical hemostasis
Cardiac arrest

Question 27

NE uses

Answer 27

Sometimes shock, but not widely used

Question 28

Isoproterenol uses

Answer 28

Stimulate heart in heart block or before implanting pacemaker

Question 29

Dopamine therapeutic uses

Answer 29

Cardiogenic shock

May cause N/V d/t dopamine

Question 30

Dobutamine therapeutic uses

Answer 30

Increases contractility but not rate

CHF associated with surgery or MI

Question 31

Phenylephrine, ephedrine

Answer 31

Alpha agonists

Use: decongestants, raise BP, dilate pupil, eye drops

Question 32

Albuterol, terbutaline

Answer 32

Beta agonists

Use: Asthma, anaphylactic shock, delay labor/relax uterus

Question 33

Caffeine, theophylline

Answer 33

Xanthines - adrenergic effects w/o acting at receptors. Bind at sleepy adenosine receptors instead
Caffeine: acts at CNS
Theophylline: acts at heart and bronchi