Section 2b Adrenergic Agonists

Question 1

what amino acid is DOPA made from?

Answer 1

Tyrosine

Question 2

What part of the catecholamine biosynthesis happens in the cytoplasm?

Answer 2

Tyrosine –> DOPA –> Dopamine

Question 3

Where does the majority (~90%) of catecholamines (NE) come from?

Answer 3

Presynaptic (re)uptake via NET

Question 4

what blocks catecholamine synthesis?

Answer 4

methyltyrosine

Question 5

what blocks catecholamine storage?

Answer 5

reserpine via VMAT - release empty vesicles

Question 6

what increases catecholamine release?

Answer 6

tyramine, amphetamine (indirect action)

Question 7

what blocks catechol. release?

Answer 7

guanethidine

Question 8

what blocks chatechol. (re) uptake presynaptically?

Answer 8

cocaine, tricyclic antidepressants via NET (indirect action)

Question 9

what blocks chatechol. metabolism?

Answer 9

MAO inhibitors

Question 10

Where are VMAT 1 and 2 found?

Answer 10

1 = peripheral
2 = CNS

Question 11

What is a NET selective blocker?

Answer 11

Atomoxetine - treatment of ADHD

Question 12

what has a mixed (direct and indirect) adrenergic agonist action?

Answer 12

ephedrine

Question 13

What is the preference of Epi vs NE for B1 and B2?

Answer 13

B1 - Epi=NE

B2 - Epi>NE

Question 14

What is the preference of Epi, NE, and Iso for a receptor?

Answer 14

Epi > NE > Iso

Question 15

What is the preference of Epi, NE, and Iso for B receptor?

Answer 15

Iso > Epi > NE

Question 16

What is the receptor preference for phenylephrine?

Answer 16

a1 > a2&raquo_space;> B

Question 17

What is the receptor preference for Clonidine?

Answer 17

a2 > a1&raquo_space;> B

Question 18

What is the receptor preference for NE and Epi?

Answer 18

NE: a1 = a2; B1&raquo_space; B2
Epi: a1 = a2; B1 = B2

Question 19

What is the receptor preference for Dobutamine? Isoproterenol? Terbutaline/Albuterol?

Answer 19

Dobutamine: B1 > B2&raquo_space; a
Isoproterenol: B1 = B2&raquo_space;a
Terbutaline/Albuterol: B2&raquo_space;> B1&raquo_space;» a

Question 20

What is the receptor preference for Fenoldopam?

Answer 20

D1&raquo_space;> D2

Question 21

What are the 4 major effects (in tissues) that a1 do?

Answer 21

1. vascular smooth muscle = vasoconstriction (increased blood pressure)
2. Pupillary dilator (radial) = contraction (pupil dilation)
3. Urinary bladder (sphincter) = contraction
4. Prostate = contraction

Question 22

What are the 2 major effects (in tissues) that a2 do?

Answer 22

1. adrenergic nerve terminals = inhibit transmitter release

2. pancreatic = decrease insulin secretion

Question 23

What are the 2 major effects (in tissues) that B1 do?

Answer 23

1. heart = increase rate and force of contraction

2. renal jux. cells = increase renin secretion

Question 24

What are the 6 major effects (in tissues) that B2 do?

Answer 24

1. respiratory smooth muscle = bronchodilation
2. uterine smooth muscle = relaxation (prego)
3. vascular skeletal muscle = vasodilation
4. urinary bladder (detrusor wall) = relaxation
5. liver = glycogenolysis, gluconeogenesis
6. pancreas = increase insulin secretion

Question 25

Major effects (in tissues) that B3 does?

Answer 25

adipose tissue = lipolysis

Question 26

What senses high blood pressure and responds with an increase in vagal tone which decreases heart rate? where is it located and how does it work?

Answer 26

baroreflex sensors/mechanism in the neck -- it is fast acting with the release of ACh in the sinoatrial node which decreases BP

Question 27

what do NE, Isoproterenol, and Epi do to systolic pressure? | and of these 3 which decreases pulse rate?

Answer 27

Epi = decreases it NE = increases it (decrease pulse rate) Isoproterenol IV = markedly decreases it

Question 28

What are adrenergic receptors and effects in teh respiratory tract? (2)

Answer 28

1. bronchodilation (B2) | 2. decongestant (a1)

Question 29

What are the adrenergic receptors and effects in the genitourinary tract? (3)

Answer 29

1. urinary continence (a1A, B2) 2. ejaculation (a1) 3. uterine relaxation in pregnant women near term (B2)

Question 30

What are the adrenergic receptors and effects in the eye? (3)

Answer 30

1. mydriasis (dilation) (a) 2. increased outflow of aqueous humor (a) 3. decreased production of aqueous humor (B antagonists)

Question 31

What do B's increase? (3)

Answer 31

lipolysis, insulin secretion, and renin secretion

Question 32

What do a2 decrease? (3)

Answer 32

lipolysis, insulin secretion, and renin secretion