Adrenergic Neuron Blockers

Question 1

alkaloid from roots of Rauwolfia

Answer 1

reserpine

Question 2

This drug blocks vesicle storage of amines by IRREVERSIBLY BLOCKING VMAT (vesicular membrane-associate transporter), depleting NE, DA, 5-HT

Answer 2

Reserpine

Question 3

Primarily used for hypertension during pregnancy

Answer 3

methyldopa

Question 4

ANB that can cause reduction in renal vascular resistance

Answer 4

methyldopa

Question 5

False neurotransmitter (Methyldopa metabolite)

Answer 5

a-methylnorepinephrine

Question 6

Methyldopa’s metabolite acts as an agonist on what receptor

Answer 6

alpha 2.

Question 7

Methyldopa inhibits what enzyme?

Answer 7

DOPA decarboxylase

decreases dopamine –> decreased NE/E –> lower BP and cause central effects

Question 8

Common A/E of methyldopa:

Answer 8

sedation

Question 9

ANB that can cause positive Coombs Test

Answer 9

methyldopa

can cause immune hemolytic reaction

Question 10

ANB that may cause or exacerbate ulcers

Answer 10

reserpine

Question 11

ANB that requires NET, uptake 1

Answer 11

guanethidine needs to be transported across the membrane by NET, uptake 1

Question 12

Sexual dysfunction, orthostatic hypotension are common side effects of

Answer 12

guanethidine

Question 13

VMAT mechanism:

Answer 13

transports NE, DA, 5-HT from synapse into presynaptic vesicles

Question 14

Uses NET 1 to accumulate in nerve ending, binding to vesicles and ultimately inhibiting NE release

Answer 14

guanethidine

Question 15

ANB with Tyramine-like effect when given IV

Answer 15

guanethidine

Question 16

CVS effect of guanethidine

Answer 16

Decreased BP (triple response)

Question 17

MAO inhibitors interaction with Tyramine intake?

Answer 17

Hypertensive crisis

MAOIs prevent metabolism of tyramine –> increased tyramine levels –> release of stored catecholmines –> excess alpha and beta stimulation

Question 18

ANB that interferes with catecholamine synthesis

Answer 18

methyltyrosine

Question 19

Uses for methyltyrosine

Answer 19

pheochromocytoma (lowers catecholamine levels)

Question 20

What drugs decrease effects of alpha 2 agonists like methyldopa

Answer 20

TCA inhibits NE reuptake, increase NE levels

alpha 2 agonists lower NE levels

Question 21

ANB that causes depression

Answer 21

Reserpine

Question 22

Highly associated with causing breast carcinoma

Answer 22

Reserpine

Question 23

Quinone intermediate

Answer 23

6-hydroxydopamine

Question 24

No clinical uses –> neurotoxic at nerve terminals causing chemical sympathetctomy

Answer 24

6-hydroxydopamine

Question 25

Inhibits NE release at adrenergic terminals
AND
used as a Class III antiarrhythmic

Answer 25

Bretylium

prototype, no longer used

Question 26

These drugs act by initially activating the ganglionic nACh (N) receptors, which is then
followed by receptor blockade

Answer 26

Depolarizing ganglionic blockers

stimulation then block (fasciculation then paralysis)

Question 27

Prototype drug for depolarizing ganglionic blockers

Answer 27

nicotine

lbeline, coniine, TMA and DMPP are other examples used experimentally

Question 28

Prototype anti-HTN drug, the first introduced

Answer 28

Hexamethonium (C6)

non-depolarizing (competitive) ganglionic blocker

Question 29

Ganglionic blocker used to improve GIT absorption

Answer 29

Mecamylamine (2ndary amine)

Question 30

Ganglionic blockers have antisympathetic effects at these organs

Answer 30

arterioles
veins
sweat glands

Question 31

Ganglionic blockers have antiparasympathetic effects here

Answer 31

Heart
Iris
Ciliary muscle
GIT
Urinary
Salivary

Question 32

Ganglionic blocker used in Tourette’s

Answer 32

Mecamylamine (2ndary amine)

Question 33

Ganglionic blocker occasionally used in hypertensive emergencies and in neurosurgery

Answer 33

Trimethaphan

Question 34

Inhibits tyrosine hydroxylase

Answer 34

methyltyrosine

Question 35

Guanethedine + pheochromocytoma

Answer 35

HTN crisis

Question 36

Guanethedine + TCAs

Answer 36

TCAs block NET 1, interfering with Guanethidine MoA

TCA inhibits guanethidine action by blocking the reuptake