Chapter 10 (SAS 1) Flashcards
1
Q
What are the endogenous catecholamines?
A
Norepinephrine, Epinephrine, and Dopamine
2
Q
Binds to a1, a2, and b1 receptors
A
Norepinephrine
3
Q
Binds to a and b receptors
A
Epinephrine
4
Q
Binds to the alpha-1. alpha-2, beta-1 receptors and also dopamine receptors
A
Dopamine
5
Q
Locations comprising alpha 1
A
Smooth muscles:
Vascular smooth muscles
Prostatic smooth muscles
Pupillary dilator muscles
Pilomotor smooth muscles
6
Q
Response of a1: Vascular smooth muscles
A
Vasoconstriction
7
Q
Response of a1: Prostatic smooth muscles
A
Contraction
8
Q
Response of a1: Pupillary dilator muscle
A
Contraction
9
Q
Response of a1: Pilomotor smooth muscles
A
Contraction
10
Q
Locations comprising alpha-2
A
Presynaptic CNS and Postsynaptic
11
Q
Response of a2: Presynaptic CNS
A
Inhibits release of NE
Consequence:
Central - Sedation and Depression
Peripheral - Vasodilation
12
Q
Response of a2: Postsynaptic
A
Vasoconstriction
13
Q
Location comprising b2
A
- Smooth Muscle (Bronchial smooth muscle, Uterine smooth muscle, Vascular smooth muscle supplying skeletal muscles)
- Skeletal Muscle
- Liver
14
Q
Locations comprising b3
A
Adipose tissues
15
Q
Response of b2: Bronchial smooth muscle
A
Bronchodilation
16
Q
Response of b2: Uterine smooth muscle
A
Relaxation (tocolysis)
17
Q
Locations comprising b1
A
Heart and Juxtaglomerular cells
18
Q
Locations comprising b1
A
Heart and Juxtaglomerular cells
19
Q
Locations comprising b1
A
Heart and Juxtaglomerular cells
20
Q
Locations comprising b1
A
Heart and Juxtaglomerular cells
21
Q
Locations comprising b1
A
Heart and Juxtaglomerular cells
22
Q
Response of b1: Heart
A
Increases cardiac output (positive chronotropic effect), Increases impulse conduction (positive dromotropic effect), and increases contraction (positive inotropic effect)
23
Q
Response of b1: Juxtaglomerular cells
A
Increase renin release
24
Q
Response of b2: Bronchial smooth muscle
A
Bronchodilation
25
Response of b1: Uterine smooth muscle
Relaxation
26
Response of b1: Vascular smooth muscle that supplies the skeletal system
Vasodilation
27
Response of b1: Skeletal muscle
Muscle contraction and Promotes potassium uptake
28
Response of b1: Liver
Activates glycogenolysis and gluconeogenesis
29
Response of b2: adipose tissue
Lipolysis
30
Nonselective a antagonist is used in the treatment of
Pheochromocytoma
31
What is pheochromocytoma?
a tumor that secretes catecholamines
32
Selective a1 antagonists is used in?
Hypertension and benign prostatic hyperplasia
33
Beta-receptor antagonists drugs are for?
Hypertension, ischemic heart disease, arrhythmias, glaucoma, and endocrinological and neurological disorders
34
Alpha receptor may be ____ or ____ in their mechanism of action
Reversible or irreversible
35
Reversible antagonists
Dissociate from the receptors wherein the block can be surmounted with sufficiently high amount of agonists
36
Examples of reversible antagonists
Phentolamine and prazosin
37
Irreversible antagonists
Do not dissociate and cannot be surmounted
38
Example of an irreversible antagonists
Phenoxybenzamine (it covalently binds to the receptors)
39
Cardiovascular effects of alpha receptor antagonists
Causes a decrease in blood pressure
40
Drug of choice for pheochromocytoma
Phenoxybenzamine
41
Drug of choice for the management of Raynaud's syndrome
Phentolamine and Tolazoline
42
Selective a1 antagonists
Prazosin, Doxazosin, Terazosin, Alfuzosin, Tamsulosin
43
Explain orthostatic hypertension
It is the lowering of blood pressure that happens when you stand up from lying or sitting down
44
Other name for orthostatic hypertension
Postural hypertension
45
What receptor are expressed in the base of the bladder and the prostate?
Alpha1 receptor
46
Blockade of alpha1 receptor results to?
Decreased flow of urine
47
Using alpha1 receptor antagonists in the bladder or in the prostate results to?
treat urinary retention due to prostatic hyperplasia
48
Inhibits reuptake of released norepinephrine
Phenoxybenzamine
49
Adverse effects of phenoxybenzamine
Orthostatic hypotension, tachycardia, nasal stuffiness, inhibition of ejaculation, fatigue, sedation, and nausea
50
Potent competitive antagonist at both a1 and a2 receptors
Phentolamine
51
Reduces peripheral resistance through blockade of a1 receptors
Phentolamine
52
Effective in the management of hypertension; highly selective for a1 receptors; relaxes both peripheral and vascular smooth muscle as well as the smooth muscles in the prostate
Prazosin
53
Another reversible a1-selective antagonist used in the treatment for hypertension; approved for use of men with BPH; has high bioavailability but is extensively metabolized; only a small fraction of unchanged drug is excreted in the urine
Terazosin
54
Also used for hypertension and BPH; differs in such a way that it has a long half-life; moderate bioavailability, and very little parent drug is excreted in the urine
Doxazosin
55
Competitive a1 antagonist; has a high affinity for a1A and a1D receptors; greater potency in inhibiting contraction in the prostate muscle
Tamsulosin
56
a1 selective quinazoline derivative that is approved for BPH; increased risk of QT prolongation in susceptible individuals
Alfuzosin
57
Resembles tamsulosin in blocking the a1A receptor and is used for BPH
Silodosin
58
Another a1 selective antagonist that has efficacy as antihypertensive
Indoramin
59
a1 antagonist that has a weak a2 agonist, and is also used in Europe for hypertension and BPH
Urapidil
60
both a1 selective and beta antagonist
Carvedilol and Labetalol
61
neuroleptic drugs; potent dopamine receptors but are also antagonists at a receptors
Chlorpromazine and haloperidol
62
antidepressant and has the capacity to block a1 receptors
Trazodone
63
ergot derivatives that causes a reversible alpha receptor blockade via a partial agonist action
Ergotamine and Dihydroergotamine
64
a2 selective antagonist and is used in the treatment of orthostatic hypotension because it inhibits the release of norepinephrine through its blockade; once widely used for erectile dysfunction; and reverses the hypertensive effect caused by a2-adrenoceptor agonists
Yohimbine
65
A tumor of the adrenal medulla or sympathetic ganglion cells
Pheochromocytoma
66
Are most useful in the preoperative management of pheochromocytoma
Alpha-receptor antagonists
67
a-adrenoceptor drugs have limited application in the management of hypertensive emergencies, but _____ has been used in this setting
Labetalol
68
Individuals with Raynaud's syndrome or excessive reversible vasopasm in the peripheral circulation do benefit from prazosin and phenoxybenzamine. However, _____ are preferable for most patients
Calcium channel blockers
69
Mechanism of action in improving urine flow
Partial reversal of smooth muscle contraction in the enlarged prostate and the bladder base
70
Has relatively little clinical usefulness and prescription drugs with this mechanisms are no longer available although the bark of yohimbine is used for erectile dysfunction (though the effectiveness is questionable)
Alpha2 receptor antagonist
71
What do beta-receptors antagonists have in common?
Antagonizing the effects of catecholamines
72
Differentiate pure antagonist, partial agonists, and inverse agonists
Pure antagonist is the occupancy of the b-receptor but causes no activation of the receptor. Partial agonist causes partial activation of the receptor. Inverse agonists stabilize the conformation of beta receptors reducing the proportion of active receptors.
73
The beta receptor antagonists differs in their ______ for b1 and b2 receptors.
Relative affinities
74
None of the clinically available beta receptors are B1-selective. Thus, the selectivity is ______, as it tends to diminish at higher drug concentration.
Dose-related
75
Most of the drugs in this class are well-absorbed after oral administration where peak concentrations occur after 1-3 hours of ingestion
Beta-receptor antagonists
76
What beta blocker undergoes extensive hepatic metabolism and its bioavailability is relatively low
Propranolol
77
____ and ___ are quite lipophilic and readily cross the BBB
Propranolol and Penbutolol
78
Major exception in beta-receptor antagonists with a half-life of approximately 10 minutes.
Esmolol
79
Excreted unchanged in the urine and has the longest half-life of any available beta-receptor antagonists
Nadolol
80
Effects of beta-receptor antagonist on the CV system
Lower blood pressure, do not cause hypotension in healthy individuals, and have prominent effects in the heart especially in the treatment of angina and chronic heart failure
81
What should the patient if she has asthma and needs to take a beta-receptor antagonist to treat her heart condition?
Beta-1 receptor antagonist
82
The mechanism of beta-receptor antagonists in reducing intraocular pressure in the eye especially in glaucoma
Decreasing aqueous humor
83
Coronary artery disease is less likely to occur if the beta blockers are ____.
Partial agonists
84
Local anesthetic action is also known as
Membrane-stabilizing action
85
Prominent effect of several B-blockers
Local anesthetic action
86
Membrane-stabilizing B blockers are not used topically in the ____.
Eye
87
Nonselective b-blocker that lacks local action but has marked class III antiarrhythmic effect
Sotalol
88
Prototypical B-blocking drug
Propranolol
89
Safer in patients who experience bronchoconstriction in response to propranolol
Metoprolol, Atenolol
90
may be preferable to patient with diabetes and peripheral vascular disease when therapy with B-blocker is required
Beta-1 selective antagonist
91
is a beta-1 selective antagonist with modest capacity to activate b2 receptors
Celiprolol
92
Ultra-short-acting b1 selective adrenoceptor antagonist that is useful in controlling supraventricular arrhythmias and etc.
Esmolol
93
Partial B agonist activity and is less likely to cause bradycardia and abnormalities in plasma lipids
Pindolol, Acebutolol, Penbutolol,
Carteolol, Oxprenolol, and Celiprolol
94
Most highly selective b1-blocker by promoting endothelial nitric oxide production
Nebivolol
95
Is a reversible adrenoceptor blocker that is available as a racemic mixture of two pairs of chiral isomers
Labetalol
96
In labetalol, the S,R isomer si _____
Potent a blocker
97
In labetalol, the R,R, isomer is ___
Potent b blocker
98
Nonselective B-blockers with the capacity to block a1-adrenergic receptors
Carvedilol, Medroxalol, Bucindolol
99
Nonselective B-blocker without local therapeutic activity which is advantageous when treating glaucoma topically
Timolol
100
A beta-blocker that is noteworthy because of its very long duration of action
Nadolol
101
____ and ___ are also used for topical ophthalmic application in glaucoma
Levobunolol and Betaxolol
102
Selective b2-blocking drug used in research
Butoxamine
