Adrenergic Pharmacology

Question 1

Characteristic sympathomimetics:  receptor specificities
Phenylephrine-
Clonidine-
NE-
Epi-
Isoproterenol-
Dopamine-

Answer 1

a1
a2
a1, b1, (a2)
a1, b1, b2, (+a2)
b1, b2
DA, a1, b1

Question 2

Agonist potencies at adrenergic receptors:
b1-
b2-
a1-
a2-

Answer 2

ISO>Epi>NE>DA
ISO>Epi»NE»DA
Epi>NE>DA»ISO
CLON>Epi>NE»ISO

Question 3

Dopamine action on receptor and effect:

At low dose, medium dose, at high dose

Answer 3

Low dose: direct action of D1 causes vasodilation, thus inc in renal, mesenteric, and cerebral vessels, lowering bp and increasing urine output.
Med: more of above, and some direct B1 agonism in heart and some indirect NE release, thus positive inotropic effect.
High: more of above, and some direct action on a1 vascular receptors and indirect NE release, thus vasoconstriction (including renal, as a1 action dominates DA receptor activation)

Question 4

Ergotamine use, what type of agonist/antagonist

Answer 4

Acute migraine, a-agonist

Question 5

Ergonovine use, what type of agonist/antagonist

Answer 5

Oxytocic, control of post-partum bleeding. a-agonist.

Question 6

Bromocriptine use, what type of agonist/antagonist

Answer 6

Hyperprolactinemia (dec prolactin), DA2 agonist. Parkinsonism, DA agonist.

Question 7

Side effects of alpha adrenergic agonists

Answer 7

HTN/HA, localized ischemia (a1), dramatic bp drop upon rapid withdrawal (a1), nervousness anxiety insomnia (if they cross BBB).

Question 8

a2 agonists act on the central control of blood pressures called what?

Answer 8

Nucleus Tractus Solitarius

Question 9

a-methyldopa: class, mech and uses

Answer 9

a2 agonist. decrease central sympathetic output, thus decreasing bp in treating htn. Tx’s shock too I think

Question 10

Clonidine: class, uses, side effects

Answer 10

a2 agonist. Tx’s htn, shock, and “super-sympathetic” state during opioid w/d. sedation and retention of water and sodium.

Question 11

Side effects of beta adrenergic agonists

Answer 11

Cardiac arrhythmia (direct from B1 activation, indirect response to lowered bp from b2-mediated vasodilation), occasional skel muscle tremor with b2-agonists

Question 12

Please look at ppt notes

Answer 12

OK

Question 13

General uses of beta-blockers

Answer 13

HTN, arrhythmias, angina pectoris, glaucoma, migraine, stage fright, +/- heart failure.

Question 14

Major side effects of beta-blockers

Answer 14

Cardiac depression (b1), bronchoconstriction (b2), fatigue nausea vomiting diarrhea, sexual dysfunction

Question 15

Uses for alpha-antagonists

Answer 15

HTN, pheo, shock, BPH

Question 16

Side effects of sympathetic blocking drugs:
postural hypotension-
nasal stuffiness-
drowsy and dizzy-
inhibition of ejaculation-
erectile dysfunction-
bradycardia-
bronchoconstriction-
metabolic alterations

Answer 16

a
a
CNS
a
b1
b1
b2
b2

Question 17

Explain why prazosin imparts less tachy and postural hypotension than the other 2 a-blockers

Answer 17

It’s selective for a1, thus a2 negative feedback can take place at the synapse of cardioaccelerator neurons in the heart, preventing too much NE release that would activate B receptors and inc HR.

Question 18

Quick blurb about each:
They are all called what?
a-methyltyrosine-
reserpine-
guanethidine-

Answer 18

Neuron-blocking drugs
mgmt of pheo
older antihypertensive, can cause bad depression
antihypertensive

Question 19

NE: selective to, actions, thx application, S.E.s

Answer 19

a1, a2, b1;
vasoconstriction, inc bp, direct incr HR, reflex decr HR;
hypotension;
htn, arrhythmias, HA

Question 20

Epi: selective to, actions, thx application, S.E.s

Answer 20

a1,a2,b1,b2;
inc HR, inc contractility, inc bp, reflex decr HR;
anaph shock, w/ local anesthetics, glaucoma;
palps, arr’s, HA, tremor

Question 21

Isoproterenol: selective to, actions, thx application, S.E.s

Answer 21

b1, b2;
dec resistance, inc CO, inc HR, bronchodilation;
bronchodilator/asthma, shock, heart block;
palps, tachyarr’s, HA

Question 22

Dobutamine: selective to, actions, thx application, S.E.s

Answer 22

b1;
inc contractility, inc HR, direct inc HR;
cardiac decomp, shock, heart block;
tachyarr’s, htn

Question 23

Albuterol & terbutaline: selective to, actions, thx application, S.E.s

Answer 23

b2;
relax bronchial & uterine sm muscle;
bronchodil/asthma, COPD;
tachy, muscle tremor

Question 24

Phenylephrine: selective to, actions, thx application, S.E.s

Answer 24

a1;
vasoconstriction;
nasal decong, postural hypotension;
htn, reflex brady

Question 25

Fenoldopam: selective to, actions, thx application, S.E.s

Answer 25

D1;
vasodilation;
hypertensive emergency, anuria;
postural hypotension

Question 26

Amphetamine: selective to, actions, thx application, S.E.s

Answer 26

Indirect-acting release of NE;
CNS stim;
ADHD;
htn, anxiety, arr’s, insomnia

Question 27

Dopamine: selective to, actions, thx application, S.E.s

Answer 27

D1, b1, a1, NE release;
vasodilation, inc GFR, inc HR, inc BP;
shock, RF, hypotension;
vasoconstriction (@high doses)

Question 28

Phentolamine & phenoxybenzamine: selective to, actions, thx application, S.E.s

Answer 28

a1, a2;
vasodilation, dec resistance, dec bp;
pheo, raynaud’s, frostbite;
postural hypotension, inhibit ejac

Question 29

Prazosin: selective to, actions, thx application, S.E.s

Answer 29

a1;
vasodilation, dec R and bp;
primary htn, bph;
postural hypotension

Question 30

Propranolol & Timolol: selective to, actions, thx application, S.E.s

Answer 30

b1, b2 (1st gen);
dec HR, contractility, CO;
angina, htn, arr’s;
brady, bronchoconstriction, sexual dysfunction

Question 31

Metoprolol & atenolol: selective to, actions, thx application, S.E.s

Answer 31

b1 (2nd gen);
dec HR, contractility, CO;
HTN, angina, arr’s, CHF;
brady, sexual dysfunction

Question 32

Carvedilol & labetalol: selective to, actions, thx application, S.E.s

Answer 32

b1, b2, a1? (3rd gen);
dec HR, dec CO;
CHF, htn;
brady, fatigue

Question 33

Betaxolol: selective to, actions, thx application, S.E.s

Answer 33

b1, a1? (3rd gen);
dec HR, dec CO;
CHF, htn;
brady