Autonomic Modulators

Question 1

Where does the synthesis of NE happen?

Answer 1

Liver, presynaptic cytoplasm, vesicles

Question 2

What part of the synthesis of NE happens in the liver?

Answer 2

Phenylalanine to tyrosine

Question 3

What part of the synthesis of NE happens in the presynapic cytoplasm?

Answer 3

tyrosine to dopa to dopamine

Question 4

What part of the synthesis of NE happens in the vesicle?

Answer 4

Dopamine to NE to epi

Question 5

What is the effect of alpha 1 agonism?

Answer 5

Increased intracellular calcium –> smooth muscle contraction, sphincter contraction, vasoconstriction, bronchoconstriction, uterine contraction

Question 6

What is the effect of alpha 2?

Answer 6

Decreased exocytosis of NTs.
Causes smooth muscle relaxation and vasodilation
CNS sedation

Question 7

What are the effects of Beta 1?

Answer 7

Increased adenylate cyclase: increased HR, contractility, and conduction

Question 8

What are the effects of Beta 2?

Answer 8

Bronchodilation
Vasodilation
Uterine relaxation 
Relaxation of bladder and gut
Increased glycogenolysis, lipolysis, gluconeogenesis and insulin release

Question 9

Which receptors does epi act on?

Answer 9

Alpha 1, Beta 1 and 2

Question 10

What are the effects of epi?

Answer 10

Increased contractility, CO, and O2 demand
Decreased SVR (B2)
Increased cerebral and coronar perfusion
Decreased splanchnic and renal perfusion

Question 11

What receptors does norepi act on?

Answer 11

Alpha 1 and Beta 1 (acts more on alpha)

Question 12

What are the effects of norepi?

Answer 12

Increased SVR, contractiliy, CO, HR

Question 13

What are the effects of dopamine at low levels?

Answer 13

Increased urine output via vasodilation of renal vessels
Decreased aldosterone
Increased CO (B1)

Question 14

What are the effects of dopamine in the moderate range (2-10 ugm)?

Answer 14

Mainly Beta effects:
Increased contractility
Coronary O2 demand is higher than supply

Question 15

What are the effects of dopamine in high doses?

Answer 15

Mostly alpha effects: vasoconstriction, bronchoconstriction, uterine constriction.
Predisposes myocardium to ventricular arrythmia

Question 16

What are the effects of ephedrine?

Answer 16

Increased CO, HR and BP

Question 17

What is the MOA of ephedrine?

Answer 17

SNS mimetic - indirectly releases NE

Question 18

What receptors is isoproterenol acting on?

Answer 18

B1 and B2

Question 19

What are the effects of isoproterenol?

Answer 19

Increased HR, contractility, O2 demand and decreased SVR.

O2 demand exceeds supply because of drop in diastolic BP

Question 20

What receptors does dobutamine act on?

Answer 20

Beta 1

Question 21

What are the effects of dobutamine?

Answer 21

Primarily increased CO and contractility

Question 22

What receptor does phenylephrine act on?

Answer 22

alpha 1

Question 23

What are the effects of phenylephrine?

Answer 23

vasoconstriction, reflex brady, increased afterload and BP

Question 24

What receptor is methyldopa acting on?

Answer 24

alpha 2

Question 25

What receptor is clonidine acting on?

Answer 25

alpha 2

Question 26

What are the effects of methyldopa?

Answer 26

Produces false NTs which activate alpha 2 receptors and causes a decrease in SNS stimulation --> vasodilation and lower BP

Question 27

What are the effects of clonidine?

Answer 27

Direct alpha 2 agonist | Sedating properties are effective for lowering anesthetic requirements intraoperatively.

Question 28

What is clonidine used for?

Answer 28

As an adjunct in regional anesthesia for increased quality an duration of nerve blocks

Question 29

What receptor does dexmedotomidine act on?

Answer 29

alpha 2

Question 30

What are the effects of dexmedetomidine?

Answer 30

More potent alpha 2 agonist than clonidine Initial HTN then brady and hypotension Sedating and analgesic lowers anesthetic requirement

Question 31

What is the MOA of nitroprusside?

Answer 31

metabolized to NO

Question 32

What are the effects of nitroprusside?

Answer 32

Vaso and venodilation Decreased afterload, preload and BP while CO and RBF are well maintained Reflex tachy Decreased O2 demand on the heart

Question 33

What are the cerebral effects of nitroprusside?

Answer 33

increased CBF and ICp

Question 34

What are the pulmonary effects of nitroprusside?

Answer 34

Dilates pulmonary vessels causing pulm. a. pressure to be lowered and decreasing the shunt fraction

Question 35

How is nitroprusside metabolized?

Answer 35

Receives an electron from hemoglobin resulting in methemoglobin and then a nitroprusside free radial --> cyanide

Question 36

What are the signs of cyanide toxicity?

Answer 36

arrythmia, metabolic acidosis, and increased mixed venous oxygen content

Question 37

What is the tx of cyanide toxicity?

Answer 37

Mechanical ventilation of 100% O2 Sodium nitrate to make methemoglobin which will bind cyanide Sodium thiosulfate to bind cyanide

Question 38

What are the effects of nitroglycerin?

Answer 38

Decreased preload through venodilation Increased coronary perfusion Antiplatelet effects

Question 39

What is a possible side effect of nitroglycerin?

Answer 39

Methemoglobinemia

Question 40

What is the MOA of hydralazine?

Answer 40

Vasodilator

Question 41

What is atropine?

Answer 41

A tertiary amine that can cross the bb barrier ad the placenta

Question 42

What is a potential side effect of atropine at toxic doses?

Answer 42

CNS stimulation: hallucination, irritability, nervousness

Question 43

What is atropine known to cause?

Answer 43

Fever

Question 44

What are the CV effects of anticholinergics?

Answer 44

Tachycardia by blocking vagal stimulation | Shortened PR interval

Question 45

What are the pulmonary effects of anticholinergics?

Answer 45

Decreased airway secretions | Relaxes bronchial smooth muscle

Question 46

What are the cerebral effects of anticholinergics?

Answer 46

Excitation or depression

Question 47

What are the GI effects of anticholinergics?

Answer 47

Decreased salivation, motility, peristalisis

Question 48

What are the GU effects of anticholinergics?

Answer 48

Urinary retention

Question 49

What are the effects of anticholinergics on sweat glands?

Answer 49

Inhibits sweat glands so may have increased basal body temp

Question 50

what are the uses of glycopyrrolate?

Answer 50

decrease salivation and respiratory secretion

Question 51

Why can't glycopyrrolate cross the bb barrier?

Answer 51

It is a quaternary structure

Question 52

What does scopolamine cause that atropine does not?

Answer 52

Sedation