Adrenergic Pharmacology

Question 1

NE receptors

Answer 1

Alpha 1
alpha 2
beta 1

Question 2

Epinephrine receptors

Answer 2

Alpha 1
Alpha 2
Beta 1
Beta 2

Question 3

Alpha 1 receptor mediated effects

Answer 3

Mydriasis
Construction of arteries and veins
Construction of GI GU sphincters
Ejaculation

Question 4

Beta 1 receptor mediated effectsa

Answer 4

Heart
Increase renin secretion
Increase lipolysis- increase FFA

Question 5

Beta 2 receptor mediated effects

Answer 5

Bronchodilation
Dilation of arteries in skeletal muscle
Increase glycogenolysis and gluconeigenesis
Increase insulin secretion
Relaxation of uterus

Question 6

Alpha 2 receptor mediated effects

Answer 6

Decrease sympathetic outflow from CNS
Decrease NE release
Decrease insulin secretion

Question 7

Most abundant urinary metabolite of NE and Epi

Answer 7

3-Methoxy-4-hydroxy-mandelic acid (VMA)

Question 8

Inhibition of tyrosine hydroxylase

Answer 8

Metyrosine- used to reduce NE Epi in pheochromocytoma

Question 9

Tyramine

Answer 9

Induced release of NE/Epi
Dietary constituent
Effects enhanced by MAOIs-hypertensive crisis

Question 10

Amphetamine

Answer 10

Release of NE/Epi

Pronounced CNS stimulation

Question 11

Cocaine

Answer 11

Inhibition of NE reuptake

Question 12

Tranylcypromine and Phenelzine

Answer 12

Inhibit MAO

Predispose patients toward hypertensive crisis

Question 13

Entacapone

Answer 13

Inhibition of COMT metabolism of levodopa

Question 14

Catecholamines

Answer 14

Dopamine
Isoproterenol
NE
EPI
Dobutamine

Rapidly metabolized
Not effective orally

Question 15

Non-catecholamine

Answer 15

Phenylephrine
Ephedrine
Amphetamine

Longer duration of action than catecholamine

Question 16

Phenylephrine

Answer 16

Selective alpha 1 receptor agonist

Vasoconstriction- increase TPR- increase BP
Reflex decrease HR

Mydriatic
Decongestant
Prolong action of local Anesthetics

Question 17

Clonidine

Answer 17

Selective alpha 2 receptor agonists

Vasodilation- decrease TPR- decrease BP
Little reflex increase HR

Hypertension
Drug addiction
ADHD

Question 18

Albuterol

Answer 18

Selective Beta 2 receptor agonists

Bronchodilation
Vasodilation- reflex increase HR

Adverse effects- cardiac stimulation at high doses

Question 19

Isoproterenol

Answer 19

Agonist at beta 1 and beta 2 receptors

Net effect: decrease TPR, decrease BP, increase HR

Bronchospasm
Cardiac arrest: +chronotrope +inotrope
Heart block

Question 20

Epinephrine

Answer 20

CV effects of low dose:
Vasodilation (beta 2 effects-decrease TPR in skeletal muscle)
Net effect: decrease TPR decrease BP increase HR

CV effects of high dose:
Vasoconstriction (alpha predominates)
Net effect: increase TPR increase BP increase HR

Anaphylaxis
Bronchospasm
Cardiac arrest
Glaucoma

Marked hyperglycemia adverse effect
Decrease insulin secretion- increase blood glucose
Increase glycogenolysis- increase blood glucose

Question 21

Norepinephrine

Answer 21

Net effect: increase TPR increase BP

Septic and cardiogenic shock

Question 22

Dobutamine

Answer 22

Used in acute CHF:
+inotrope- increase CO

Adverse effects:
Arrhythmias, increase myocardial O2 consumption, increase AV nodal conduction

Question 23

Dopamine

Answer 23

Dilation of renal, splanchnic, cerebral and coronary vessels

Causes release of NE/Epi

Treat shock and acute CHF

Question 24

Low dose DA

Answer 24

D1 receptor mediated selective vasodilation of renal and splanchnic vessels

Question 25

Moderate doses DA

Answer 25

D1 receptor mediated vasodilation- decrease TPR | Direct and reflex Beta 1 receptor cardiac effects- increase HR, increase CO

Question 26

High dose DA

Answer 26

Alpha receptor vasoconstriction- increase TPR Beta 1 receptor cardiac effects- increase HR Increase BP

Question 27

Pseudoephedrine

Answer 27

Effects due to direct action at Adrenergic receptors + release of NE Decongestant Insomnia Hypertension

Question 28

Phenoxybenzamine

Answer 28

Non competitive block of alpha 1 and alpha 2 receptors Vasodilation- decrease TPR Reflex increase HR Long lasting Preoperative or chronic Tx pheochromocytoma with Beta blockers

Question 29

Phentolamine

Answer 29

Competitively inhibits alpha 1 and alpha 2 receptors Short duration of action Must be administered IV Hypertensive crisis Surgical removal of pheochromocytoma Reversible vasospastic disease

Question 30

Doxazosin

Answer 30

Specific alpha 1 receptor antagonists Arteriolar dilation- decrease TPR- decrease BP Relaxation of bladder sphincter Benign prostatic hypertrophy Hypertension “First dose syncope” precipitous decrease BP

Question 31

Tamsulosin

Answer 31

Selective alpha receptor antagonists Relaxation of bladder sphincter Can cause orthostatic hypotension

Question 32

Propranolol

Answer 32

Competitively inhibits Beta 1 and Beta 2 ``` CV effects: Decrease automaticity- decrease HR- decrease CO Decrease contractility- decrease CO Decrease myocardial O2 consumption Decrease AV nodal conduction velocity Decrease coronary blood flow ``` Non-CV effects: Inhibition of glycogenolysis Decrease intraocular pressure in glaucoma Decrease lipolysis- decrease FFA, increase triglycerides Decrease HDL

Question 33

Propranolol uses

Answer 33

``` Hypertension Chronic stable angina Arrhythmias Post MI Hyperthyroidism Pheochromocytoma Migraine Idiopathic hypertrophic subaortic stenosis Stage fright Essential tremors ```

Question 34

Metoprolol

Answer 34

Beta 1 receptor antagonist Preferred for diabetes, Raynauds syndrome, COPD

Question 35

Esmolol

Answer 35

Short acting cardioselective Beta blocker Metabolized by red cell esterase Used as anti-arrhythmic

Question 36

Carvedilol

Answer 36

Alpha 1, beta 1, beta 2 receptor antagonists Decrease TPR Increase HDL Hypertension and CHF

Question 37

Nebivolol

Answer 37

Cardioselective Beta 1 block + NO mediated vasodilation Decrease TPR Hypertension