Adrenergic Antagonists- T2

Question 1

alpha adrenergic receptor antagonists may be classified as

Answer 1

reversible competitive antagonists and irreversible competitive alpha-adrenergic antagonists

Question 2

phentolamine is a

Answer 2

non-selective (both alpha 1 and 2) reversible competitive alpha-adrenergic receptor antagonists.

Question 3

prazosin, doxazosin, and terazosin are

Answer 3

alpha1 selective reversible competitive alpha-adrenergic receptor antagonists

Question 4

tamsulosin and silodosin (rapaflo) are

Answer 4

alpha1A/D selective reversible competitive alpha-adrenergic receptor antagonists

Question 5

phenoxybenzamine is

Answer 5

a irreversible competitive non selective alpha adrenergic antagonist

Question 6

4 piperazinyl quinazolines

Answer 6

prazosin, terazosin, doxazosin, alfuzosin

Question 7

3 indoles

Answer 7

yohimbine, indoramin, silodosin

Question 8

alpha1 and 2 adrenoceptors are responsible for the

Answer 8

maintenance of TPR and maintain pressure.

Question 9

in many patients with essential HTN, TPR may be abnormally elevated due to

Answer 9

increased alpha-adrenergic receptor stimulation.

Question 10

the 6 alpha-adrenergic receptor subtypes

Answer 10

1a, 1b, 1d, 2a, 2b, 2c

Question 11

agents that antagonize both alpha1 and 2 tend to be

Answer 11

less efficacious in lowering BP than alpha1 selective

Question 12

blockade of alpha2 adrenoceptors will cause

Answer 12

enhanced release of NE at the sympathetic neurons leading to excess adrenoceptor stimulation.

Question 13

alpha2 blockage causes veno___ which leads to__

Answer 13

venodilation leading to a reduction in preload and then reduces SV.

Question 14

why would we want to give a selective alpha antagonist opposed to non selective

Answer 14

giving a selective reduces the peripheral resistance, if it doesn’t have selectivity, we won’t have effects that come from antagonizing a specific alpha receptor.

Question 15

prazosin and htn tx

Answer 15

a alpha1 selective antagonist that is prone to hepatic metabolism, has the shortest half life and primarily eliminated in the bile. if the patient has renal impairment you would want to use this.

Question 16

doxazosin and terazosin in htn tx.

Answer 16

alpha1 selective antagonists have more renal eliminated of the parent compound and longer half life of elimination, would want to use these if the pt had liver failure.

Question 17

antagonism of alpha1 adrenoceptors result in

Answer 17

dilation of arteries, arterioles, and veins.

Question 18

arteriolar dilation results in

Answer 18

decreased after load (decreased TPR)

Question 19

afterload is

Answer 19

the pressure that the heart has to work against.

Question 20

venous dilation causes

Answer 20

decreased preload

Question 21

decreased preload decreases

Answer 21

myocardial stretch and thus the CO.

Question 22

efferent arteriolar dilation causes

Answer 22

decrease GFR which causes decrease Na in DCT and causes increased renin release.

Question 23

what agents have equivalent BP lowering capacity to alpha1 selective antagonists

Answer 23

Ca channel blockers and thiazides

Question 24

adverse effects of alpha1 selective adrenergic receptor antagonists

Answer 24

hypotension (first dose or orthostatic), dizziness, HA, congestion, impaired ejaculation and miosis

Question 25

the lest well tolerated alpha1 selective antagonist

Answer 25

prazosin

Question 26

alpha1 selective antagonists contraindicated in pts with

Answer 26

right heart failure or cardiac valvular stenosis.

Question 27

how do alpha blockers make right heart failure worse

Answer 27

right HF is the right ventricle not ejecting the right amount of blood, too little filling, not enough stretch. alpha blockers decrease the preload, which makes RHF worse.

Question 28

alternative use for alpha1 selective antagonists other than HTN

Answer 28

benign prostatic hyperplasia

Question 29

tamsulosin is selective for what receptor

Answer 29

alpha1a

Question 30

___ receptors predominate in the vasculature

Answer 30

alpha1b

Question 31

why would you give terazosin for HTN and BPH?

Answer 31

because it isn't subtype selective like flomax is.

Question 32

what is phenoxybenamines MOA and what is its therapeutic use

Answer 32

alkylates alpha 1 &2 adrenoceptors to cause decrease in receptors available for activation by catecholamines. used for pheochromocytoma where excess catecholamine production results in dangerously high BP

Question 33

yohimbine is a selective

Answer 33

alpha2 receptor blocker that produces increase BP via CNS effects.

Question 34

4 non selective b-receptor antagonists

Answer 34

propranolol, nadolol, timolol, pindolol

Question 35

4 b1 receptor selective antagonists

Answer 35

metoprolol, atenolol, esmolol, acebutolol

Question 36

2 beta and alpha1 selective antagonists

Answer 36

labetalol and carvedilol

Question 37

what drug is a beta blocker with additional effects

Answer 37

bystolic, dilates blood vessels by NO release.

Question 38

5 general things that distinguish members of the beta adrenergic receptor antagonist class

Answer 38

b1 vs non selectivity, partial agonism, alpha adrenoceptor blocking, lipid solubility, and inverse agonists.

Question 39

b1 vs non-selectivity

Answer 39

propranolol has equivalent affinities for the 2 receptors while metoprolol, esmolol and atenolol show greater b1 receptor affinity

Question 40

partial agonism with beta adrenergic antagonists

Answer 40

propranolol is an antagonist with no ability to active b-receptors; while pindolol and acebutolol behave more as a partial agonist

Question 41

alpha-adrenoceptor blocking activity in regards to beta-adrenergic antagonist

Answer 41

most agents in this class are relatively b-selective however labetalol and carvedilol have significant alpha1 blocking activity.

Question 42

lipid solubility

Answer 42

more lipophilic agents have greater CNS effects. this is why propranolol can be used for stage fright.

Question 43

generally b-blockade causes

Answer 43

greater decreases in HR and contractility during sympathetic NS activity.

Question 44

major effect of b-blockade

Answer 44

decrease cardiac rate and contractility to decrease Co and thereby MBP

Question 45

initially ___ may rise due to beta2-blockade and/or reflex baroreceptor mechanism to maintain BP

Answer 45

TPR

Question 46

partial agonists or alpha blocking activity may produce less increase in

Answer 46

TPR

Question 47

b-antagonists also ___ renin release..

Answer 47

decrease. causing less circulating angiotensin II.

Question 48

how do mixed antagonists decrease BP

Answer 48

by slpha1 blockage in the vasculature as well as beta-blockade in the heart.

Question 49

partial b-receptor agonists produce smaller decreases in __ and may be preferred in pts with

Answer 49

CO. preferred in pts with bradycardia or decreased cardiac reserve.

Question 50

pharmacological adverse effects of b-adrenergic antagonists

Answer 50

HF, bradycardia, angina after withdrawal, bronchoconstriction in asthmatics, fatigue, insomnia, depression.