Adrenergic System Flashcards Preview

Disease/Therapeutics 2 Exam 1 > Adrenergic System > Flashcards

Flashcards in Adrenergic System Deck (96):
1

What receptors does NE interact with?

alpha 1
alpha 2
beta 1

2

What receptors does Epi interact with?

alpha 1
alpha 2
beta 1
beta 2

3

Alpha 1 Receptor Mediated EFFECTS (4)

Sympathomimetic:
1. Mydriasis
2. Constricts arteries/veins
3. Constricts GI/GU sphincters
4. Ejaculation/Orgasm

4

Beta 1 Receptor Mediated EFFECTS (5)

Symapthomimetic
1. INC HR (heart)
2. INC Contraction (heart)
3. INC Conduction Velocity (heart)
4. INC Renin Secretion (Vasoconstricts/ INC BP)
5. INC Lipolysis (INC FFA)

5

Beta 2 Receptor Mediated EFFECTS (5)

Sympathomimetic
1. Bronchodilation
2. Dilates arteriers in skeletal muscle
3. INC blood sugar
4. INC insulin secretion
5. Relaxes Uterus

6

Alpha 2 Recepter Mediated EFFECTS (3)

SYMPATHOLYTIC
1. DEC Sympathetics from CNS (DEC BP -- vasodilation)
2. DEC NE Release
3. DEC Insulin Secretion

7

What is the most important factor for termination the action of neuronally released NE?

ACTIVE REUPTAKE

8

What is the most abundant urinary metabolite of NE and EPI? What usually acts on NE and EPI before it's excreted?

3-Methoxy-4-Hydroxy-Mandelic Acid
(VMA)
- BOTH MAO and COMT

9

Monoamine Oxidase (MAO) metabolizes what?

-Metabolizes many monoamines (non-specific)
-Protects against circulating and EXOGENOUS BIOLOGICALLY ACTIVE AMINES

10

Catechol-O-Methyl-Transferase (COMT) metabolizes what?

-Specifically metabolizes catechols
-Imp for metabolizing CIRCULATING CATECHOLAMINES

11

What is the rate limiting step in the synthesis of NE and EPI?

Tyrosine --> Dopa by Tyrosine Hydroxylase

12

What drug inhibits tyrosine hydroxylase? (Therefore decreasing formation of NE and EPI from Tyrosine)

Metyrosine (Desmer)

13

When is Metyrosine used specifically?

Pheochromocytoma

14

What 2 drugs cause rapid release of NE from nerve terminal?

Tyramine
Amphetamine

15

What is amphetamine (adderall) prescribed for?

ADHD
Narcolepsy

16

What is a specific adverse effect of Amphetamine?

Marked CNS effects due to pronounced CNS stimulation

17

Why should you NOT combine Tyramine with MAOIs?

Enhanced action --> hypertensive crisis

18

What is the MOA for cocaine?

Inhibits NE reuptake
INC NE effects
Sympathomimetic

19

What 2 drugs INHIBIT MAOs? (MAOIs)

1. Tranylcypromine
2. Phenelzine
(and others)

20

MAOI's predispose patients toward what? How?

Hypertensive Crisis
- Increase the levels of circulating dietary amines which leads to HYPERTENSION

21

What drug INHIBITS COMT?

Entacapone

22

What is Entacapone used for?

Adjunctive therapy with levodopa for PARKINSONISM

23

What are the 3 possible mechanisms of action for Adrenergic Receptor AGONISTS?

1. Direct interaction of drug with adrenergic receptor
2. Indirect action via drug induced release of NE/EPI (endogenously)
3. Mixed direct and indirect

24

What are the 5 catecholamines?

DINED
Dopamine
Isoproterenol
NE
EPI
Dobutamine

25

Are catecholamines effective if taken orally?

NO

26

Describe catecholamines

Rapidly Metabolized
Short duration of action
Metabolized by COMT
OH on C3 and C4 of Benzene Ring

27

What are the 3 mentioned NON-Catecholamines?

Phenylephrine
Ephedrine
Amphetamine

28

Describe non-catecholamines

Longer duration of action than catecholamines
Effective orally

29

What is the SELECTIVE Alpha 1 Receptor AGONIST?

Phenylephrine

30

What is the SELECTIVE Alpha 2 Receptor AGONIST?

Clonidine

31

What is the SELECTIVE Beta 2 Receptor AGONIST?

Albuterol

32

What is Phenylephrine used for? (3)

Myadritic (dilates eyes)
Decongestant (vasoconstrics nasal mucosa)
Prolong action of local anesthetics (local vasoconstrict)

33

What is Clonidine used for? (3)

Hypertension (reduces sympath from CNS)
Drug Addiction
ADHD

34

What is Albuterol used for? (2)

Reverse Bronchospasm
Bronchial Asthma (bronchodilator)

35

What are 3 adverse effects of Clonidine?

1. Hypertensive crisis upon sudden withdrawl
2. Sedation
3. Sexual Dysfunction

36

What are 2 adverse effects and 2 contraindications for Albuterol AND Isoproterenol?

AE:
1. Cardia Stimulation (LOST selectivity at high doses causing beta 1 activation) -- arrhythmias, engine
2. Tremor

Contra:
1. Tachyarrythmia
2. Hyperthyroidism

37

Isoproterenol is an AGONIST where?

Beta 1 AND Beta 2 Receptors

38

What is Isoproterenol used for?

1. Bronchospasm (when inhaled)
2. Cardia Arrest (+ chronotrope, +ionotrope)
3. Heart Block (INC AV conduction)

39

What are the overall effects of Isoproterenol?

1. Bronchodilation
2. DEC BP
3. INC HR

40

Epinephrine (Adrenaline, Epipen) is what type of drug?

AGONIST at alpha 1, alpha 2, beta 1, and beta 2 receptors

41

What are the cardiovascular effects of a LOW dose of Epinephrine? (similar to physiological levels during fight/flight response)

Vasodilation (DEC BP)
Tachycardia (INC HR)

42

What are the cardiovascular effects of HIGH dose of Epinephrine?

Vasoconstriction (INC BP)
Tachycardia (INC HR)

43

What are 5 uses for Epinephrine?

1. Anaphylaxis (dec mediator release, bronchodilates)
2. Bronchospasm (bronchodilation)
3. Cardiac Arrest (+chronotrope, +ionotrope)
4. Prolong local anesthetics (local vasoconstriction)
5. Glaucoma (INC aqueous outflow)

44

What are 4 adverse effects of Epinephrine?

1. MARKED HypERglycemia (DEC insulin, Inc glycogenolysis)
2. Cardiac Stimulation (arrythmia, angina)
3. Vasoconstriction (hypertension)
4. CNS Stimulation (Inc respiration, tremor)

45

What are the contraindications Epinephrine?

Tachyarrythmias
Hyperthyroidism
INC Toxicity with MAOIs

46

Norepinephrine (noradrenaline) is what type of drug?

AGONIST at alpha 1, alpha 2, and beta 1 receptors

47

What are the cardiac effects of Norepinephrine?

Vasoconstriction (INC BP)
+- HR (dose dependent)

48

What is Norepinephrine used for?

Septic Shock
Cardiogenic Shock
(vasoconstrics + ionotrope)

49

What are the adverse effects of Norepinephrine?

Arrythmia
Angina
Hypertension (vasoconstriction)

50

What are the contraindications for Norepinephrine?

Tachyarrythmias
Hyperthyroidism
Hypertension
INC toxicity with MAOIs
INC toxicity with cocaine (reuptake inhibitors)

51

What do we use Dobutamine for? Why?

Acute CHF (chronic heart failure)

It is a +ionotrope (INC CO)

52

What are the adverse effects of Dobutamine?

Arrythmias
INC Myocardial O2 consumption
INC AV Nodal Conduction
Hypertension (in some pts.)

53

Dopamine has what type of actions?

-Direct AGONIST at Dopaminergic D1 Receptors (dilation of renal, splanchnic, cerebral, and coronary vessels)
-AGONIST at alpha 1, alpha 2, and beta 1 receptors
-Causes release of NE/EPI (adverse effects are similar to NE/EPI)

54

Effects of LOW doses of Dopamine

D1-receptor mediated selective vasodilation of renal and splanchnic vessels

55

Effects of MODERATE doses of Dopamine

D1-receptor mediated vasodilation (DEC TPR)
INC HR
INC CO
+ or - BP

56

Effects of HIGH doses of Dopamine

alpha receptor vasoconstriction (INC TPR)
beta 1 receptor (INC HR)
INC BP

57

What is Dopamine used for? (low to moderate doses) (2)

Shock
Acute CHF

58

Pseudoephedrine (Sudafed)

Direct action at Adrenergic Receptors
Release of NE
Vasoconstriction

59

Uses of Pseudoephedrine

Decongestant (vasoconstriction of nasal mucosa)

60

Adverse effects of Pseudoephedrine (2)

Hypertension
Insomnia

61

What are the actions of Adrenergic Receptor ANTAGONISTS? (2)

Inhibit actions of endogenous NE and EPI at receptor sites
Inhibit actions of exogenously administered drugs mediated by adrenergic receptors

62

Effects of Alpha 1 Receptor INHIBITION (3)

Vasodilation (DEC BP)
Relaxation of Bladder Sphincter
DEC Sexual Function

63

Effects of Alpha 2 Receptor INHIBITION

Sympathomimetic Response
INC BP
INC HR
INC sympath from CNS
INC NE release

64

Phenozybenzamine is what type of drug?

NON-Competitive Block of alpha 1 and alpha 2 receptors

65

What do we use Phenoxybenzamine for?

-Preoperative or chronic therapy for PHEOCHROMOCYTOMA (along with Beta blockers)
- treatment of reversible vasospastic disease

66

What are the effects caused by taking Phenoxybenzamine?

Vasodilation (DEC TPR)
INC HR
** LONG LASTING**
Slow onset
Effective Orally

67

What are the contraindications/adverse effects of Phenoxybenzamine?

Tachycardia, arrhythmias, angina
Orthostatic Hypotension
Sexual Dysfunction

68

What type of drug is Phentolamine?

Competitive inhibitor of alpha 1 and alpha 2 receptors
(similar to phenoxybenzamine)

69

What makes Phentolamine different from Phenoxybenzamine?

Faster onset
Shorter duration of action
MUST BE GIVE IV

70

What do we use Phentolamine for?

Hypertensive Crisis
During surgical removal of pheochromocytoma
Reversible Vasospastic Disease (frostbite)

71

What are the 2 relatively specific alpha 1 receptor ANTAGONISTS?

1. Doxazosin (Prazosin)
2. Tamsulosin

72

What are the effects of Doxazosin?

Arteriolar Dilation (DEC BP)
Relaxation of Bladder Spincter

73

What do we use Doxazosin for?

1. Benign Prostatic Hypertrophy
2. Hypertension

74

What are the adverse effects of Doxazosin?

"First Dose Syncope" -- (DEC BP)
* only in volume depleted patients -- so begin it at night*

75

What do we use Tamsulosin for?

Relaxation of bladder sphincter in Benign Prostatic Hypertrophy.
*Selective inhibition of alpha 1a receptors my provide some SELECTIVITY for sphincter*

76

Effects of Beta 1 Receptor Inhibition (5)

DEC HR (heart)
DEC Contraction (heart)
DEC Conduction Velocity (heart)
DEC Renin Secretion
DEC Lipolysis
** more marked in states with high sympathetic tone like exercise, hyperthyroidism, anxiety**

77

Effects of Beta 2 Receptor Inhibition

Bronchoconstriction
DEC Glycogenolysis
INC TPR

78

If a drug has a lower lipid solubility, what side effects can this decrease?

CNS side effects

79

What receptor must I block to be "cardioselective"?

Beta 1

80

What are the 2 Non-Specific Beta Receptor Antagonists?

Propranolol
Timolol

81

How does Propranolol work?

Competitively inhibits beta 1 and beta 2

82

What are the cardiovascular effects of Propranolol? (7)

DEC HR
DEC CO
DEC myocardial O2 consumption
DEC AV nodal conduction velocity
Long term = DEC BP
DEC Renin
DEC Coronary Blood flow

83

What are the non-CV effects of Propranolol? (5)

Bronchoconstriction
Inhibits glycogenolysis in response to EPI (diabetics**)
DEC Intraocular Pressure in Glaucoma
DEC Lipolysis (INC Triglycerides)
DEC HDL

84

What are the therapeutic uses of Propranolol?

Hypertension
Chronic Stable Angina
Arrythmias
Post MI
Hyperthyroidism
Pheochromocytoma
Migraine
Idiopathic Hypertrophic Subaortic Stenosis (IHSS)
Stage Fright
Essential Tremors

85

Adverse Effects of Propranolol?

Bronchoconstriction
Bradycardia
Hypotension
DEC Myocardial Contractility
AV Block
Cold Extremities (aggravates Raynaud's)
Dec Exercise Tolerance
Sexual Dysfunction
Aggravates Variant Angina
INC Plasma Triglycerides
CNS (fatigue, lethargy, vivid dreams, insomnia, depression)

Sudden withdrawal = hypertension, angina, MI, sudden death

86

In what 2 populations should you avoid Propranolol?

1. Asthma/COPD Patients
2. Diabetics (causes hypoglycemia, inhibition of tachycardia in response to hypoglycemia)

87

Timolol is used for what?

Glaucoma

88

What are the 2 CARDIOSELECTIVE Beta 1 Receptor Antagonists?

1. Metoprolol (atenolol)
2. Esmolol

89

Metoprolol has what MOA?

Inhibits Beta 1 receptors

90

Metoprolol is preferred over non-specific beta blockers in what patient populations? (3)

1. Diabetes
2. Raynaud's Syndrome
3. COPD

91

Metoprolol is used for what?

Similar uses as Propranolol
CHF

92

What is special about Esmolol? (3)

Very short acting
Metabolized by red cell ESTERASE
Used as Antiarrhythmic (IV ONLY)

93

How does Carvedilol work?

Non-specific beta blocker
Specific alpha 1 blocker

94

What are the effects of Carvedilol?

Antioxidant Activity
DEC TPR (DEC BP)
INC HDL

95

What is Carvedilol used for?

Hypertension
CHF

96

How does Nebivolol work?

Cardioselective B1 blocker
NO-mediated Vasodilation
Used for Hypertension (can cause a more prominent hypotension than carvedilol)