Autonomic Pharm I

Question 1

primary result of alpha-1 activation?

Answer 1

vasoconstriction by activation of smooth muscle

Question 2

alpha-1 specific antagonists?

Answer 2

Doxazosin, Terazosin, Prazosin

Question 3

balanced alpha-1/alpha-2 antagonists?

Answer 3

Phenoxybenzamine, Phentolamine

Question 4

subtypes of alpha-1 receptors?

Answer 4

alpha-1a, alpha-1b, alpha-1d

Question 5

location of alpha-1a receptors?

Answer 5

bladder neck and prostate, blockade can improve symptoms of BPH and improve urine flow

Question 6

Stimulation of alpha-1 receptors induces vasoconstriction in these in vessels

Answer 6

vasculature of the skeletal muscle and skin, and the splachnic vessels

Question 7

synaptic location of alpha-1 receptors?

Answer 7

post-synaptic membrane, mediates downstream events

Question 8

synaptic location of alpha-2 receptors?

Answer 8

pre-synaptic terminal, functions as auto-receptor to terminate further NE release

Question 9

activation of alpha-2 receptors produces?

Answer 9

agonists produce bradycardia and hypotension, they terminate further NE release

Question 10

blockade of alpha-1 receptors causes?

Answer 10

lower blood pressure, prevents NE-stimulated smooth muscle contraction in the vasculature

Question 11

Which alpha antagonist requires more than one daily dosing?

Answer 11

Prazosin

Question 12

Alpha antagonist most correlated with first dose orthostatic hypotension?

Answer 12

Prazosin

Question 13

Alpha antagonists that are more likely to cause sinus tachycarida?

Answer 13

Non-specific blockers, by virtue of augmenting action of endogenous NE release by inhibiting alpha-2

Question 14

Phenoxybenzamine mechanism?

Answer 14

Binds covalently (me last you long time) to both alpha-1 and alpha-2

Question 15

Phenoxybenzamine effect on blood pressure?

Answer 15

reduction via vasodilation, but less substantially than alpha-1 specific antagonists due to increased cardiac output seen with alpha-2 inhibition

Question 16

Indications of Phenoxybenzamine?

Answer 16

Pheochromocytoma and “off label” use for Raynaud’s Syndrome

Question 17

Mechanism of Phentolamine?

Answer 17

Non-specific, competitive alpha antagonist (short-acting)

Question 18

Cardio-stimulation with Phentolamine?

Answer 18

Yes, due to antagonism of alpha-2

Question 19

Phentolamine at low doses?

Answer 19

Blood pressure RISES due to cardio-stimulatory effect predominating

Question 20

Phentolamine at high doses?

Answer 20

Blood pressure falls due to alpha-1 mediated vasodilation

Question 21

Indications for Phentolamine?

Answer 21

Pheochromocytoma and hypertensive emergency (only hospital use)

Question 22

Precipitous fall in blood pressure causes what response?

Answer 22

Baroreceptors initiate sympathetic stimulation of the heart and subsequent tachycardia

Question 23

Are alpha antagonists very common in the treatment of HTN?

Answer 23

No, they are no longer used much due to better drugs

Question 24

Main locations of beta receptors?

Answer 24

the heart (B1), skeletal muscle vasculature (B2), bronchial smooth muscle (B2), and juxtaglomerular apparatus in the kidney (B1)

Question 25

Stimulation of beta-2 in vasculature of muscles causes?

Answer 25

inhibitory action, prevents calcium entry into vascular smooth muscle--> relaxation/increased perfusion of skeletal muscle (vasodilation)

Question 26

Stimulation of beta-1 causes?

Answer 26

acceleration of heart rate and increase in contractile force

Question 27

subtype of beta receptors in juxtaglomerular cells?

Answer 27

Beta-1

Question 28

stimulation of beta-1 receptors in the kidney causes?

Answer 28

release of renin, which eventually makes angiotensin II and induce potent vasoconstriction

Question 29

What is sympathomimetic activity?

Answer 29

the drug agent functions as a weak partial agonist that will provide some cardio-stimulation (but prevent excessive stimulation via endogenous NE/E)

Question 30

What types of patients would sympathomimetic drugs be useful?

Answer 30

the elderly, stroke patients, and others very susceptible to bradycardia caused by beta-blockers

Question 31

Most common CNS adverse effect seen in highly lipophilic beta antagonists?

Answer 31

Bad dreams

Question 32

Beta antagonists with names "A-M"

Answer 32

beta-1 selective

Question 33

Beta antagonists with names "N-T"

Answer 33

non-selective

Question 34

Beta antagonists ending in "ILOL" and "ALOL"

Answer 34

possess extended actions in preventing alpha-mediated reflex vasoconstriction (act as alpha 1 antagonists)

Question 35

Beta antagonist that also blocks calcium channels?

Answer 35

Carvedilol, Betaxolol

Question 36

Mechanism of beta-blocker antihypertensive effect?

Answer 36

Inhibit stimulation of renin production by catecholamines. Inhibition of presynaptic B-adrenoceptors that reduces sympathetic vasoconstrictor activity

Question 37

How must beta blockers be discontinued? Why?

Answer 37

They must be tapered off the medication. Chronic therapy causes up-regulation of the beta receptors that can cause rebound HTN if the medication is abruptly d/c

Question 38

Effects of Propranolol overdose?

Answer 38

Seizures and coma (highly lipophilic)

Question 39

Effects of Sotalol overdose?

Answer 39

prolongs the QT interval and can cause ventricular fibrillation and Torsade de Pointes

Question 40

Rescue drug therapy used in beta antagonist overdose?

Answer 40

Glucagon or high-dose Insulin/Glucose (cannot use Beta agonists, receptors are blocked)

Question 41

Non-specific beta blockers are contraindicated in?

Answer 41

patients with asthma (advised against in those with COPD)

Question 42

Beta receptor with important role in tx of bronchospasm?

Answer 42

Beta-2

Question 43

Beta blockers used cautiously in these patients?

Answer 43

Diabetics, B-1 antagonism masks hypoglycemic induced tachycardia--> patients unaware of low Blood sugar Also patients on the borderline of decompensating CHF

Question 44

Effects of Beta-2 antagonism on glucose metabolism?

Answer 44

inhibits hepatic glycogenolysis and pancreatic glucagon release

Question 45

Beta blocker effect on Lipid profile?

Answer 45

can increase TAGs and decrease HDL; little/no effect on total cholesterol or LDL